Publications
21.
Espey, Jessica M.; Tatem, Andrew J.; Thomson, Dana R.
Disappearing people: A global demographic data crisis threatens public policy Journal Article
In: Science, vol. 388, iss. 6753, pp. 1277-1280, 2025.
Abstract | Links | BibTeX | Tags:
@article{nokey,
title = {Disappearing people: A global demographic data crisis threatens public policy},
author = {Jessica M. Espey and Andrew J. Tatem and Dana R. Thomson},
url = {https://doi.org/10.1126/science.adx8683},
doi = {10.1126/science.adx8683},
year = {2025},
date = {2025-06-19},
journal = {Science},
volume = {388},
issue = {6753},
pages = {1277-1280},
abstract = {Every day, decisions that affect our lives—such as where to locate hospitals and how to allocate resources for schools—depend on knowing how many people live where and who they are; for example, their ages, occupations, living conditions, and needs. Such core demographic data in most countries come from a census, a count of the population usually conducted every 10 years. But something alarming is happening to many of these critical data sources. As widely discussed at the United Nations (UN) Statistical Commission meeting in New York in March, fewer countries have managed to complete a census in recent years. And even when they are conducted, censuses have been shown to undercount members of certain groups in important ways. Redressing this predicament requires investment and technological solutions alongside extensive political outreach, citizen engagement, and new partnerships.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Every day, decisions that affect our lives—such as where to locate hospitals and how to allocate resources for schools—depend on knowing how many people live where and who they are; for example, their ages, occupations, living conditions, and needs. Such core demographic data in most countries come from a census, a count of the population usually conducted every 10 years. But something alarming is happening to many of these critical data sources. As widely discussed at the United Nations (UN) Statistical Commission meeting in New York in March, fewer countries have managed to complete a census in recent years. And even when they are conducted, censuses have been shown to undercount members of certain groups in important ways. Redressing this predicament requires investment and technological solutions alongside extensive political outreach, citizen engagement, and new partnerships.
22.
Visée, Corentin; Morlighem, Camille; Nnanatu, Chibuzor Christopher
In: Women’s Health, vol. 21, 2025.
Abstract | Links | BibTeX | Tags:
@article{nokey,
title = {A Robust Cross-Sectional Assessment of the Impacts of COVID-19 Pandemic on the Prevalence of Female Genital Mutilation Among 0–14 Years Old Girls in Nigeria},
author = {Corentin Visée and Camille Morlighem and Chibuzor Christopher Nnanatu },
url = {https://doi.org/10.1177/17455057241311948},
year = {2025},
date = {2025-05-26},
journal = {Women’s Health},
volume = {21},
abstract = {Female genital mutilation (FGM) is a human rights violation that still affects more than 3 million girls aged 0–14 years each year. To achieve the Sustainable Development Goal 2030 agenda, efforts have been made at the local, national and international levels to end the practice by the year 2030. However, the recent COVID-19 pandemic may have reversed the progress made due to increased rates of early marriage of girls, violence against children and school closures during lockdowns. Although some surveys have examined changes in FGM prevalence over the COVID-19 period, changes at the national and sub-national levels among 0–14 years old girls have not been quantified.
This study aimed to understand the potential impacts of the COVID-19 pandemic on the likelihood of FGM among girls aged 0–14 years, and whether it affected progress towards the elimination of FGM.
We used Bayesian hierarchical regression models implemented within the integrated nested Laplace approximations frameworks.
We modelled the likelihood and prevalence of FGM among girls aged 0–14 years before and after the COVID-19 pandemic in Nigeria, with respect to individual- and community-level characteristics, using Bayesian hierarchical models. We used the 2018 Demographic and Health Survey as the pre-COVID-19 period and the 2021 Multiple Indicator Cluster Survey as the post-COVID-19 period.
At the state level, FGM prevalence varied geographically and increased by 23% and 27% in the northwestern states of Katsina and Kana, respectively. There were 11% increase in Kwara and 14% increase in Oyo. However, at the national level, the prevalence of FGM was found to decrease from 19.5% to 12.3% between 2018 and 2021. Cultural factors were identified as the key drivers of FGM among 0–14 years old girls in Nigeria. The changes in the likelihood of girls undergoing FGM across the two time periods also varied across ethnic and religious groups following COVID-19 pandemic.
Our findings highlight that FGM is still a social norm in some states/regions and groups in Nigeria, thereby highlighting the need for a continued but accelerated FGM interventions throughout the country.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Female genital mutilation (FGM) is a human rights violation that still affects more than 3 million girls aged 0–14 years each year. To achieve the Sustainable Development Goal 2030 agenda, efforts have been made at the local, national and international levels to end the practice by the year 2030. However, the recent COVID-19 pandemic may have reversed the progress made due to increased rates of early marriage of girls, violence against children and school closures during lockdowns. Although some surveys have examined changes in FGM prevalence over the COVID-19 period, changes at the national and sub-national levels among 0–14 years old girls have not been quantified.
This study aimed to understand the potential impacts of the COVID-19 pandemic on the likelihood of FGM among girls aged 0–14 years, and whether it affected progress towards the elimination of FGM.
We used Bayesian hierarchical regression models implemented within the integrated nested Laplace approximations frameworks.
We modelled the likelihood and prevalence of FGM among girls aged 0–14 years before and after the COVID-19 pandemic in Nigeria, with respect to individual- and community-level characteristics, using Bayesian hierarchical models. We used the 2018 Demographic and Health Survey as the pre-COVID-19 period and the 2021 Multiple Indicator Cluster Survey as the post-COVID-19 period.
At the state level, FGM prevalence varied geographically and increased by 23% and 27% in the northwestern states of Katsina and Kana, respectively. There were 11% increase in Kwara and 14% increase in Oyo. However, at the national level, the prevalence of FGM was found to decrease from 19.5% to 12.3% between 2018 and 2021. Cultural factors were identified as the key drivers of FGM among 0–14 years old girls in Nigeria. The changes in the likelihood of girls undergoing FGM across the two time periods also varied across ethnic and religious groups following COVID-19 pandemic.
Our findings highlight that FGM is still a social norm in some states/regions and groups in Nigeria, thereby highlighting the need for a continued but accelerated FGM interventions throughout the country.
This study aimed to understand the potential impacts of the COVID-19 pandemic on the likelihood of FGM among girls aged 0–14 years, and whether it affected progress towards the elimination of FGM.
We used Bayesian hierarchical regression models implemented within the integrated nested Laplace approximations frameworks.
We modelled the likelihood and prevalence of FGM among girls aged 0–14 years before and after the COVID-19 pandemic in Nigeria, with respect to individual- and community-level characteristics, using Bayesian hierarchical models. We used the 2018 Demographic and Health Survey as the pre-COVID-19 period and the 2021 Multiple Indicator Cluster Survey as the post-COVID-19 period.
At the state level, FGM prevalence varied geographically and increased by 23% and 27% in the northwestern states of Katsina and Kana, respectively. There were 11% increase in Kwara and 14% increase in Oyo. However, at the national level, the prevalence of FGM was found to decrease from 19.5% to 12.3% between 2018 and 2021. Cultural factors were identified as the key drivers of FGM among 0–14 years old girls in Nigeria. The changes in the likelihood of girls undergoing FGM across the two time periods also varied across ethnic and religious groups following COVID-19 pandemic.
Our findings highlight that FGM is still a social norm in some states/regions and groups in Nigeria, thereby highlighting the need for a continued but accelerated FGM interventions throughout the country.
23.
Cleary, Eimear; Atuhaire, Fatumah; Sorichetta, Alessandro; Ruktanonchai, Nick; Ruktanonchai, Cori; Cunningham, Alexander; Pasqui, Massimiliano; Schiavina, Marcello; Melchiorri, Michele; Bondarenko, Maksym; Shepherd, Harry E R; Padmadas, Sabu S; Wesolowski, Amy; Cummings, Derek A T; Tatem, Andrew J; Lai, Shengjie
In: PLOS Global Public Health, vol. 5, iss. 4, no. e0003431, 2025.
Abstract | Links | BibTeX | Tags:
@article{nokey,
title = {Comparing lagged impacts of mobility changes and environmental factors on COVID-19 waves in rural and urban India: A Bayesian spatiotemporal modelling study},
author = {Eimear Cleary and Fatumah Atuhaire and Alessandro Sorichetta and Nick Ruktanonchai and Cori Ruktanonchai and Alexander Cunningham and Massimiliano Pasqui and Marcello Schiavina and Michele Melchiorri and Maksym Bondarenko and Harry E R Shepherd and Sabu S Padmadas and Amy Wesolowski and Derek A T Cummings and Andrew J Tatem and Shengjie Lai},
url = {https://doi.org/10.1371/journal.pgph.0003431},
doi = {10.1371/journal.pgph.0003431},
year = {2025},
date = {2025-04-30},
journal = {PLOS Global Public Health},
volume = {5},
number = {e0003431},
issue = {4},
abstract = {Previous research in India has identified urbanisation, human mobility and population demographics as key variables associated with higher district level COVID-19 incidence. However, the spatiotemporal dynamics of mobility patterns in rural and urban areas in India, in conjunction with other drivers of COVID-19 transmission, have not been fully investigated. We explored travel networks within India during two pandemic waves using aggregated and anonymized weekly human movement datasets obtained from Google, and quantified changes in mobility before and during the pandemic compared with the mean baseline mobility for the 8-week time period at the beginning of 2020. We fit Bayesian spatiotemporal hierarchical models coupled with distributed lag non-linear models (DLNM) within the integrated nested Laplace approximation (INLA) package in R to examine the lag-response associations of drivers of COVID-19 transmission in urban, suburban and rural districts in India during two pandemic waves in 2020-2021. Model results demonstrate that recovery of mobility to 99% that of pre-pandemic levels was associated with an increase in relative risk of COVID-19 transmission during the Delta wave of transmission. This increased mobility, coupled with reduced stringency in public intervention policy and the emergence of the Delta variant, were the main contributors to the high COVID-19 transmission peak in India in April 2021. During both pandemic waves in India, reduction in human mobility, higher stringency of interventions, and climate factors (temperature and precipitation) had 2-week lag-response impacts on the of COVID-19 transmission, with variations in drivers of COVID-19 transmission observed across urban, rural and suburban areas. With the increased likelihood of emergent novel infections and disease outbreaks under a changing global climate, providing a framework for understanding the lagged impact of spatiotemporal drivers of infection transmission will be crucial for informing interventions.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Previous research in India has identified urbanisation, human mobility and population demographics as key variables associated with higher district level COVID-19 incidence. However, the spatiotemporal dynamics of mobility patterns in rural and urban areas in India, in conjunction with other drivers of COVID-19 transmission, have not been fully investigated. We explored travel networks within India during two pandemic waves using aggregated and anonymized weekly human movement datasets obtained from Google, and quantified changes in mobility before and during the pandemic compared with the mean baseline mobility for the 8-week time period at the beginning of 2020. We fit Bayesian spatiotemporal hierarchical models coupled with distributed lag non-linear models (DLNM) within the integrated nested Laplace approximation (INLA) package in R to examine the lag-response associations of drivers of COVID-19 transmission in urban, suburban and rural districts in India during two pandemic waves in 2020-2021. Model results demonstrate that recovery of mobility to 99% that of pre-pandemic levels was associated with an increase in relative risk of COVID-19 transmission during the Delta wave of transmission. This increased mobility, coupled with reduced stringency in public intervention policy and the emergence of the Delta variant, were the main contributors to the high COVID-19 transmission peak in India in April 2021. During both pandemic waves in India, reduction in human mobility, higher stringency of interventions, and climate factors (temperature and precipitation) had 2-week lag-response impacts on the of COVID-19 transmission, with variations in drivers of COVID-19 transmission observed across urban, rural and suburban areas. With the increased likelihood of emergent novel infections and disease outbreaks under a changing global climate, providing a framework for understanding the lagged impact of spatiotemporal drivers of infection transmission will be crucial for informing interventions.
24.
Wariri, Oghenebrume; Dotse-Gborgbortsi, Winfred; Agbla, Schadrac C; Jah, Hawanatu; Cham, Mamady; Jawara, Ba Foday; Bittaye, Mustapha; Nyassi, Momodou T; Marena, Musa; Sanneh, Sainey; Janneh, Mariama; Kampmann, Beate; Banke-Thomas, Aduragbemi; Lawn, Joy E; Okomo, Uduak
Beyond proximity: an observational study of stillbirth rates and emergency obstetric and newborn care accessibility in The Gambia Journal Article
In: BMJ Global Health, 2025.
Abstract | Links | BibTeX | Tags:
@article{nokey,
title = {Beyond proximity: an observational study of stillbirth rates and emergency obstetric and newborn care accessibility in The Gambia},
author = {Oghenebrume Wariri and Winfred Dotse-Gborgbortsi and Schadrac C Agbla and Hawanatu Jah and Mamady Cham and Ba Foday Jawara and Mustapha Bittaye and Momodou T Nyassi and Musa Marena and Sainey Sanneh and Mariama Janneh and Beate Kampmann and Aduragbemi Banke-Thomas and Joy E Lawn and Uduak Okomo },
url = {https://doi.org/10.1136/bmjgh-2024-016579},
year = {2025},
date = {2025-04-03},
journal = {BMJ Global Health},
abstract = {Stillbirths are disproportionately concentrated in sub-Saharan Africa, where geographical accessibility to basic/comprehensive emergency obstetric and newborn care (BEmONC and CEmONC) significantly influences maternal and perinatal outcomes. This study describes stillbirth rates within healthcare facilities in The Gambia and examines their distribution in relation to the geographical accessibility of these facilities.
We analysed 97 276 births recorded between 1 January 2013 and 31 December 2018, from 10 major public healthcare facilities in The Gambia. To standardise definitions, stillbirths were defined as fetal deaths with a birth weight of ≥500 g. Fresh stillbirths were reclassified as intrapartum, and macerated stillbirths were reclassified as antepartum. Linear regression with cubic splines was used to model trends, and AccessMod software estimated travel times to facilities.
Among recorded births, 5.1% (4873) were stillbirths, with an overall stillbirth rate of 51.3 per 1000 births (95% CI: 27.5 to 93.6). Intrapartum stillbirths accounted for 53.8% (27.6 per 1000 births; 95% CI: 14.4 to 49.8). Fully functional CEmONC facilities reported the highest stillbirth rates, including the National Teaching Hospital (101.7 per 1000 births, 95% CI: 96.8 to 106.8). Approximately 42.8%, 58.9% and 68.3% of women aged 15–49 lived within a 10, 20 and 30 min travel time, respectively, to fully functional CEmONC facilities, where high stillbirth rates were concentrated.
In The Gambia, intrapartum stillbirth rates remain alarmingly high, even in geographically accessible CEmONC facilities. Inadequate documentation of fetal heart rate on admission hampers accurate classification, complicating targeted interventions. Ensuring that EmONC-designated facilities—particularly those providing BEmONC services—are fully functional with essential equipment, trained staff and robust referral systems, while enhancing the timeliness and quality of obstetric care, is crucial to reducing stillbirth rates.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Stillbirths are disproportionately concentrated in sub-Saharan Africa, where geographical accessibility to basic/comprehensive emergency obstetric and newborn care (BEmONC and CEmONC) significantly influences maternal and perinatal outcomes. This study describes stillbirth rates within healthcare facilities in The Gambia and examines their distribution in relation to the geographical accessibility of these facilities.
We analysed 97 276 births recorded between 1 January 2013 and 31 December 2018, from 10 major public healthcare facilities in The Gambia. To standardise definitions, stillbirths were defined as fetal deaths with a birth weight of ≥500 g. Fresh stillbirths were reclassified as intrapartum, and macerated stillbirths were reclassified as antepartum. Linear regression with cubic splines was used to model trends, and AccessMod software estimated travel times to facilities.
Among recorded births, 5.1% (4873) were stillbirths, with an overall stillbirth rate of 51.3 per 1000 births (95% CI: 27.5 to 93.6). Intrapartum stillbirths accounted for 53.8% (27.6 per 1000 births; 95% CI: 14.4 to 49.8). Fully functional CEmONC facilities reported the highest stillbirth rates, including the National Teaching Hospital (101.7 per 1000 births, 95% CI: 96.8 to 106.8). Approximately 42.8%, 58.9% and 68.3% of women aged 15–49 lived within a 10, 20 and 30 min travel time, respectively, to fully functional CEmONC facilities, where high stillbirth rates were concentrated.
In The Gambia, intrapartum stillbirth rates remain alarmingly high, even in geographically accessible CEmONC facilities. Inadequate documentation of fetal heart rate on admission hampers accurate classification, complicating targeted interventions. Ensuring that EmONC-designated facilities—particularly those providing BEmONC services—are fully functional with essential equipment, trained staff and robust referral systems, while enhancing the timeliness and quality of obstetric care, is crucial to reducing stillbirth rates.
We analysed 97 276 births recorded between 1 January 2013 and 31 December 2018, from 10 major public healthcare facilities in The Gambia. To standardise definitions, stillbirths were defined as fetal deaths with a birth weight of ≥500 g. Fresh stillbirths were reclassified as intrapartum, and macerated stillbirths were reclassified as antepartum. Linear regression with cubic splines was used to model trends, and AccessMod software estimated travel times to facilities.
Among recorded births, 5.1% (4873) were stillbirths, with an overall stillbirth rate of 51.3 per 1000 births (95% CI: 27.5 to 93.6). Intrapartum stillbirths accounted for 53.8% (27.6 per 1000 births; 95% CI: 14.4 to 49.8). Fully functional CEmONC facilities reported the highest stillbirth rates, including the National Teaching Hospital (101.7 per 1000 births, 95% CI: 96.8 to 106.8). Approximately 42.8%, 58.9% and 68.3% of women aged 15–49 lived within a 10, 20 and 30 min travel time, respectively, to fully functional CEmONC facilities, where high stillbirth rates were concentrated.
In The Gambia, intrapartum stillbirth rates remain alarmingly high, even in geographically accessible CEmONC facilities. Inadequate documentation of fetal heart rate on admission hampers accurate classification, complicating targeted interventions. Ensuring that EmONC-designated facilities—particularly those providing BEmONC services—are fully functional with essential equipment, trained staff and robust referral systems, while enhancing the timeliness and quality of obstetric care, is crucial to reducing stillbirth rates.
25.
Johnson, Matthew; Adewole, Wole Ademola; Alegana, Victor; Utazi, C. Edson; McGrath, Nuala; Wright, James
A scoping review of the methods used to estimate health facility catchment populations for child health indicators in sub‑Saharan Africa Journal Article
In: Population Health Metrics, vol. 23, iss. 11, no. 11, 2025.
Abstract | Links | BibTeX | Tags:
@article{nokey,
title = {A scoping review of the methods used to estimate health facility catchment populations for child health indicators in sub‑Saharan Africa},
author = {Matthew Johnson and Wole Ademola Adewole and Victor Alegana and C. Edson Utazi and Nuala McGrath and James Wright
},
doi = {10.1186/s12963-025-00374-0},
year = {2025},
date = {2025-03-03},
urldate = {2025-03-03},
journal = {Population Health Metrics},
volume = {23},
number = {11},
issue = {11},
abstract = {Evidence indicating persistent geographic inequalities in health outcomes signifies a need for routine subnational monitoring of health-related Sustainable Development Goal targets in sub-Saharan Africa. Health facilities may be an appropriate subnational unit for monitoring purposes, but a lack of suitable demographic data complicates the production of baseline facility-level population denominators against which progress can be reliably measured. This scoping review aimed to map the methods and data sources used to estimate health facility catchment areas and translate them to population denominators for child health indicators in the region.
Peer-reviewed research publications and grey literature reports were identified by searching bibliographic databases and relevant organisational websites. The inclusion criteria required that studies were conducted in sub-Saharan Africa since January 2000, described quantitative method(s) for estimating health facility catchment areas and/or population denominators, and focussed on children as the population of interest. Following title/abstract then full text screening of search results, relevant data were extracted using a standard form. Thematic analysis was undertaken to extract themes and present a narrative synthesis.
Overall, 33 research publications and 3 grey literature reports were included. Of these, only 7 research studies and 1 technical guidance document outlined aims explicitly framed around methods development and/or evaluation. Studies increasingly estimated catchment areas using complex geostatistical or travel time-based modelling approaches rather than simpler proximity metrics, and produced denominators by intersecting catchment boundaries with gridded population surfaces rather than aggregating area-based administrative counts. Few studies used data produced by or describing health facilities to link estimation methods to service utilisation patterns, inter-facility competition or facility characteristics.
There is a need for catchment population estimation methods that can be scaled to national-level facility networks and replicated across the region. This could be achieved by leveraging routinely collected health data and other readily available and nationally consistent data sources. Future methodological development should emphasise modern geostatistical approaches drawing upon the relative strengths of multiple data sources and capturing the range of spatial, supply-side, individual-level and environmental factors with potential to influence catchments’ extent, shape and demographic composition.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Evidence indicating persistent geographic inequalities in health outcomes signifies a need for routine subnational monitoring of health-related Sustainable Development Goal targets in sub-Saharan Africa. Health facilities may be an appropriate subnational unit for monitoring purposes, but a lack of suitable demographic data complicates the production of baseline facility-level population denominators against which progress can be reliably measured. This scoping review aimed to map the methods and data sources used to estimate health facility catchment areas and translate them to population denominators for child health indicators in the region.
Peer-reviewed research publications and grey literature reports were identified by searching bibliographic databases and relevant organisational websites. The inclusion criteria required that studies were conducted in sub-Saharan Africa since January 2000, described quantitative method(s) for estimating health facility catchment areas and/or population denominators, and focussed on children as the population of interest. Following title/abstract then full text screening of search results, relevant data were extracted using a standard form. Thematic analysis was undertaken to extract themes and present a narrative synthesis.
Overall, 33 research publications and 3 grey literature reports were included. Of these, only 7 research studies and 1 technical guidance document outlined aims explicitly framed around methods development and/or evaluation. Studies increasingly estimated catchment areas using complex geostatistical or travel time-based modelling approaches rather than simpler proximity metrics, and produced denominators by intersecting catchment boundaries with gridded population surfaces rather than aggregating area-based administrative counts. Few studies used data produced by or describing health facilities to link estimation methods to service utilisation patterns, inter-facility competition or facility characteristics.
There is a need for catchment population estimation methods that can be scaled to national-level facility networks and replicated across the region. This could be achieved by leveraging routinely collected health data and other readily available and nationally consistent data sources. Future methodological development should emphasise modern geostatistical approaches drawing upon the relative strengths of multiple data sources and capturing the range of spatial, supply-side, individual-level and environmental factors with potential to influence catchments’ extent, shape and demographic composition.
Peer-reviewed research publications and grey literature reports were identified by searching bibliographic databases and relevant organisational websites. The inclusion criteria required that studies were conducted in sub-Saharan Africa since January 2000, described quantitative method(s) for estimating health facility catchment areas and/or population denominators, and focussed on children as the population of interest. Following title/abstract then full text screening of search results, relevant data were extracted using a standard form. Thematic analysis was undertaken to extract themes and present a narrative synthesis.
Overall, 33 research publications and 3 grey literature reports were included. Of these, only 7 research studies and 1 technical guidance document outlined aims explicitly framed around methods development and/or evaluation. Studies increasingly estimated catchment areas using complex geostatistical or travel time-based modelling approaches rather than simpler proximity metrics, and produced denominators by intersecting catchment boundaries with gridded population surfaces rather than aggregating area-based administrative counts. Few studies used data produced by or describing health facilities to link estimation methods to service utilisation patterns, inter-facility competition or facility characteristics.
There is a need for catchment population estimation methods that can be scaled to national-level facility networks and replicated across the region. This could be achieved by leveraging routinely collected health data and other readily available and nationally consistent data sources. Future methodological development should emphasise modern geostatistical approaches drawing upon the relative strengths of multiple data sources and capturing the range of spatial, supply-side, individual-level and environmental factors with potential to influence catchments’ extent, shape and demographic composition.
26.
Sylla, El Hadji Malick; Fall, Ndeye Awa; Dotse-Gborgbortsi, Winfred; Sandie, Arsène Brunelle; Gueye, Barrel Sow; Senghor, Diarra Bousso; Cissé, Birane; Bocoum, Fadima Yaya; Sy, Ibrahima Ousmane; Faye, Cheikh
Beyond physical accessibility, bypassing health facilities offering caesarean section: insights from women in Dakar’s slums Journal Article
In: BMJ Open, vol. 15, 2025.
Abstract | Links | BibTeX | Tags:
@article{nokey,
title = {Beyond physical accessibility, bypassing health facilities offering caesarean section: insights from women in Dakar’s slums },
author = {El Hadji Malick Sylla and Ndeye Awa Fall and Winfred Dotse-Gborgbortsi and Arsène Brunelle Sandie and Barrel Sow Gueye and Diarra Bousso Senghor and Birane Cissé and Fadima Yaya Bocoum and Ibrahima Ousmane Sy and Cheikh Faye},
doi = {10.1136/bmjopen-2024-088606},
year = {2025},
date = {2025-02-14},
journal = {BMJ Open},
volume = {15},
abstract = {The study examines the geographic accessibility of Comprehensive Emergency Obstetric Care (CEmONC) among women residing in the slums of Dakar.
Design: The study is a cross-sectional geographic analysis of caesarean care utilisation in health facilities offering the service in Dakar.
Setting: The study was conducted in urban slum areas in Dakar.
Participants: 763 women living in urban slums who had undergone a caesarean section in six health facilities in Dakar between July and December 2022.
Outcome measures: The proportion of women bypassing the nearest health facility and travel time to health facilities.
Key findings: show that most women in Dakar’s urban slums live within 5min from a health facility offering caesarean services, with an average travel time of 6.3min. However, 44.3% bypassed nearby facilities, often travelling outside their district. Medical referral was the primary reason for bypassing (43.2%), followed by the search for higher quality care (13.5%) and reliance on family or social networks (14.9%). Only a small proportion (1.4%) cited more affordable treatment costs as a reason for bypassing.
Conclusion: Despite the good geographical accessibility of health facilities offering caesarean sections in Dakar, many women bypass nearby facilities due to medical referrals and the search for higher quality care, resulting in increased travel time and costs. Strengthening the quality and capacity of local health centres in urban slums is crucial to minimising unnecessary bypassing and ensuring timely access to essential obstetric services.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The study examines the geographic accessibility of Comprehensive Emergency Obstetric Care (CEmONC) among women residing in the slums of Dakar.
Design: The study is a cross-sectional geographic analysis of caesarean care utilisation in health facilities offering the service in Dakar.
Setting: The study was conducted in urban slum areas in Dakar.
Participants: 763 women living in urban slums who had undergone a caesarean section in six health facilities in Dakar between July and December 2022.
Outcome measures: The proportion of women bypassing the nearest health facility and travel time to health facilities.
Key findings: show that most women in Dakar’s urban slums live within 5min from a health facility offering caesarean services, with an average travel time of 6.3min. However, 44.3% bypassed nearby facilities, often travelling outside their district. Medical referral was the primary reason for bypassing (43.2%), followed by the search for higher quality care (13.5%) and reliance on family or social networks (14.9%). Only a small proportion (1.4%) cited more affordable treatment costs as a reason for bypassing.
Conclusion: Despite the good geographical accessibility of health facilities offering caesarean sections in Dakar, many women bypass nearby facilities due to medical referrals and the search for higher quality care, resulting in increased travel time and costs. Strengthening the quality and capacity of local health centres in urban slums is crucial to minimising unnecessary bypassing and ensuring timely access to essential obstetric services.
Design: The study is a cross-sectional geographic analysis of caesarean care utilisation in health facilities offering the service in Dakar.
Setting: The study was conducted in urban slum areas in Dakar.
Participants: 763 women living in urban slums who had undergone a caesarean section in six health facilities in Dakar between July and December 2022.
Outcome measures: The proportion of women bypassing the nearest health facility and travel time to health facilities.
Key findings: show that most women in Dakar’s urban slums live within 5min from a health facility offering caesarean services, with an average travel time of 6.3min. However, 44.3% bypassed nearby facilities, often travelling outside their district. Medical referral was the primary reason for bypassing (43.2%), followed by the search for higher quality care (13.5%) and reliance on family or social networks (14.9%). Only a small proportion (1.4%) cited more affordable treatment costs as a reason for bypassing.
Conclusion: Despite the good geographical accessibility of health facilities offering caesarean sections in Dakar, many women bypass nearby facilities due to medical referrals and the search for higher quality care, resulting in increased travel time and costs. Strengthening the quality and capacity of local health centres in urban slums is crucial to minimising unnecessary bypassing and ensuring timely access to essential obstetric services.
27.
Ismailakhunova, Saida; Purevjav, Avralt-Od; Byambasuren, Tsenguunjav; Qader, Sarchil
Exploring Geospatial-Based Approaches to Develop a Pre-Census National Sampling Frame in Armenia Technical Report
2025.
Abstract | Links | BibTeX | Tags:
@techreport{nokey,
title = {Exploring Geospatial-Based Approaches to Develop a Pre-Census National Sampling Frame in Armenia},
author = {Saida Ismailakhunova and Avralt-Od Purevjav and Tsenguunjav Byambasuren and Qader,Sarchil },
url = {http://documents.worldbank.org/curated/en/099435501162526801},
doi = {10.1596/1813-9450-11039},
year = {2025},
date = {2025-01-16},
issue = {World Bank Policy Research Working Paper},
abstract = {The lack of a workable and accurate national sampling frame is one of the methodological constraints in conducting representative national surveys. It undermines policy and research efforts in many developing countries, particularly those experiencing significant internal displacement and relocation due to territorial and military conflicts. This paper addresses this issue by constructing the first digitized national sampling frame in Armenia, a conflict-affected developing country, where reliable and accessible national sampling frames for household and individual surveys are severely limited. The first-ever sensible digitized urban and rural classification boundaries in the country have been created for the sampling frame. The paper constructs a national sampling frame that meets international standards based on the pre-census enumeration areas tool, leveraging a semi-automatic and resource-efficient approach and the most recent data available. The generated national sampling frame offers several advantages over the existing potential sampling frames in the country, which are based on census settlements, electoral precincts, grid sampling, and old census enumeration areas. This new frame is applied to conducting the World Bank’s “Listening to Armenia” survey, demonstrating its potential for other socioeconomic surveys in the country. The method can also be employed to generate and update national sampling frames in other countries more efficiently, given that manually generating both the digitized and non-digitized national sampling frames requires substantial financial and non-financial resources.},
keywords = {},
pubstate = {published},
tppubtype = {techreport}
}
The lack of a workable and accurate national sampling frame is one of the methodological constraints in conducting representative national surveys. It undermines policy and research efforts in many developing countries, particularly those experiencing significant internal displacement and relocation due to territorial and military conflicts. This paper addresses this issue by constructing the first digitized national sampling frame in Armenia, a conflict-affected developing country, where reliable and accessible national sampling frames for household and individual surveys are severely limited. The first-ever sensible digitized urban and rural classification boundaries in the country have been created for the sampling frame. The paper constructs a national sampling frame that meets international standards based on the pre-census enumeration areas tool, leveraging a semi-automatic and resource-efficient approach and the most recent data available. The generated national sampling frame offers several advantages over the existing potential sampling frames in the country, which are based on census settlements, electoral precincts, grid sampling, and old census enumeration areas. This new frame is applied to conducting the World Bank’s “Listening to Armenia” survey, demonstrating its potential for other socioeconomic surveys in the country. The method can also be employed to generate and update national sampling frames in other countries more efficiently, given that manually generating both the digitized and non-digitized national sampling frames requires substantial financial and non-financial resources.
28.
Johnson, Matthew; Adewole, Wole Ademola; Alegana, Victor; Utazi, C Edson; McGrath, Nuala; Wright, James
A scoping review of the methods used to estimate health facility catchment populations for child health indicators in sub-Saharan Africa Journal Article
In: Population Health Metrics, vol. 23, no. 1, pp. 1–37, 2025.
BibTeX | Tags:
@article{johnson2025scopingc,
title = {A scoping review of the methods used to estimate health facility catchment populations for child health indicators in sub-Saharan Africa},
author = {Matthew Johnson and Wole Ademola Adewole and Victor Alegana and C Edson Utazi and Nuala McGrath and James Wright},
year = {2025},
date = {2025-01-01},
journal = {Population Health Metrics},
volume = {23},
number = {1},
pages = {1–37},
publisher = {Springer},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
29.
Amouzou, Agbessi; Barros, Aluisio J D; Requejo, Jennifer; Faye, Cheikh; Akseer, Nadia; Bendavid, Eran; Blumenberg, Cauane; Borghi, Josephine; Baz, Sama El; Federspiel, Frederik; Ferreira, Leonardo Z; Hazel, Elizabeth; Heft-Neal, Sam; Hellwig, Franciele; Liu, Li; Maïga, Abdoulaye; Munos, Melinda; Pitt, Catherine; Shawar, Yusra Ribhi; Shiffman, Jeremy; Tam, Yvonne; Walker, Neff; Akilimali, Pierre; Alkema, Leontine; Behanzin, Paoli; Binyaruka, Peter; Bhutta, Zulfiqar; Blanchard, Andrea; Blencowe, Hannah; Bradley, Ellen; Brikci, Nouria; Caicedo-Velásquez, Beatriz; Costello, Anthony; Dotse-Gborgbortsi, Winfred; Arifeen, Shams El; Ezzati, Majid; Freedman, Lynn P; Guillot, Michel; Hanson, Claudia; Heidkamp, Rebecca; Huicho, Luis; Izugbara, Chimaraoke; Jiwani, Safia S; Kabiru, Caroline; Kiarie, Helen; Kinney, Mary; Kirakoya-Samadoulougou, Fati; Lawn, Joy; Madise, Nyovani; Mady, Gouda Roland Mesmer; Masquelier, Bruno; Melesse, Dessalegn; Nilsen, Kristine; Perin, Jamie; Ram, Usha; Romanello, Marina; Saad, Ghada E; Sharma, Sudha; Sidze, Estelle M; Spiegel, Paul; Tappis, Hannah; Tatem, Andrew J; and others,
The 2025 report of the Lancet Countdown to 2030 for women's, children's, and adolescents' health: tracking progress on health and nutrition Journal Article
In: The Lancet, vol. 405, iss. 10488, no. 10488, pp. 1505–1554, 2025.
Abstract | Links | BibTeX | Tags:
@article{amouzou20252025,
title = {The 2025 report of the Lancet Countdown to 2030 for women's, children's, and adolescents' health: tracking progress on health and nutrition},
author = {Agbessi Amouzou and Aluisio J D Barros and Jennifer Requejo and Cheikh Faye and Nadia Akseer and Eran Bendavid and Cauane Blumenberg and Josephine Borghi and Sama El Baz and Frederik Federspiel and Leonardo Z Ferreira and Elizabeth Hazel and Sam Heft-Neal and Franciele Hellwig and Li Liu and Abdoulaye Maïga and Melinda Munos and Catherine Pitt and Yusra Ribhi Shawar and Jeremy Shiffman and Yvonne Tam and Neff Walker and Pierre Akilimali and Leontine Alkema and Paoli Behanzin and Peter Binyaruka and Zulfiqar Bhutta and Andrea Blanchard and Hannah Blencowe and Ellen Bradley and Nouria Brikci and Beatriz Caicedo-Velásquez and Anthony Costello and Winfred Dotse-Gborgbortsi and Shams El Arifeen and Majid Ezzati and Lynn P Freedman and Michel Guillot and Claudia Hanson and Rebecca Heidkamp and Luis Huicho and Chimaraoke Izugbara and Safia S Jiwani and Caroline Kabiru and Helen Kiarie and Mary Kinney and Fati Kirakoya-Samadoulougou and Joy Lawn and Nyovani Madise and Gouda Roland Mesmer Mady and Bruno Masquelier and Dessalegn Melesse and Kristine Nilsen and Jamie Perin and Usha Ram and Marina Romanello and Ghada E Saad and Sudha Sharma and Estelle M Sidze and Paul Spiegel and Hannah Tappis and Andrew J Tatem and and others},
doi = {10.1016/S0140-6736(25)00151-5},
year = {2025},
date = {2025-01-01},
urldate = {2025-01-01},
journal = {The Lancet},
volume = {405},
number = {10488},
issue = {10488},
pages = {1505–1554},
publisher = {Elsevier},
abstract = {In line with previous progress reports by Countdown to 2030 for Women's, Children's, and Adolescents' Health, this report analyses global and regional trends and inequalities in health determinants, survival, nutritional status, intervention coverage, and quality of care in reproductive, maternal, newborn, child and adolescent health (RMNCAH) and nutrition, as well as country health systems, policies, financing, and prioritisation. The focus is on low-income and middle-income countries (LMICs) where 99% of maternal deaths and 98% of child and adolescent deaths (individuals aged 0–19 years) occur, with special attention to sub-Saharan Africa and South Asia.
Recognising the urgency of reaching the Sustainable Development Goal (SDG) for health, SDG 3, and health-related targets by 2030, the report assesses whether the momentum needed to reach these goals has been sustained, accelerated, stagnated, or regressed in comparison with the Millennium Development Goal (MDG) period (2000–15). Although most health and health-related indicators continue to show progress, there has been a notable slowdown in the rate of improvement after 2015, falling well short of the pace needed to achieve the 2030 SDG targets. This deceleration in pace contrasts sharply with the aspired grand convergence in health, characterised by drastic reductions in mortality and RMNCAH inequalities, which was expected to occur during the SDG period based on the assumption that the spectacular progress achieved during the MDG period would continue unabated. Multiple threats, external and internal to the RMNCAH health community, must be addressed to safeguard the gains in RMNCAH and nutrition and to accelerate progress. Furthermore, a large gap between sub-Saharan Africa, especially West and Central Africa, and other parts of the world persists for many indicators, necessitating further prioritisation of this region.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In line with previous progress reports by Countdown to 2030 for Women's, Children's, and Adolescents' Health, this report analyses global and regional trends and inequalities in health determinants, survival, nutritional status, intervention coverage, and quality of care in reproductive, maternal, newborn, child and adolescent health (RMNCAH) and nutrition, as well as country health systems, policies, financing, and prioritisation. The focus is on low-income and middle-income countries (LMICs) where 99% of maternal deaths and 98% of child and adolescent deaths (individuals aged 0–19 years) occur, with special attention to sub-Saharan Africa and South Asia.
Recognising the urgency of reaching the Sustainable Development Goal (SDG) for health, SDG 3, and health-related targets by 2030, the report assesses whether the momentum needed to reach these goals has been sustained, accelerated, stagnated, or regressed in comparison with the Millennium Development Goal (MDG) period (2000–15). Although most health and health-related indicators continue to show progress, there has been a notable slowdown in the rate of improvement after 2015, falling well short of the pace needed to achieve the 2030 SDG targets. This deceleration in pace contrasts sharply with the aspired grand convergence in health, characterised by drastic reductions in mortality and RMNCAH inequalities, which was expected to occur during the SDG period based on the assumption that the spectacular progress achieved during the MDG period would continue unabated. Multiple threats, external and internal to the RMNCAH health community, must be addressed to safeguard the gains in RMNCAH and nutrition and to accelerate progress. Furthermore, a large gap between sub-Saharan Africa, especially West and Central Africa, and other parts of the world persists for many indicators, necessitating further prioritisation of this region.
Recognising the urgency of reaching the Sustainable Development Goal (SDG) for health, SDG 3, and health-related targets by 2030, the report assesses whether the momentum needed to reach these goals has been sustained, accelerated, stagnated, or regressed in comparison with the Millennium Development Goal (MDG) period (2000–15). Although most health and health-related indicators continue to show progress, there has been a notable slowdown in the rate of improvement after 2015, falling well short of the pace needed to achieve the 2030 SDG targets. This deceleration in pace contrasts sharply with the aspired grand convergence in health, characterised by drastic reductions in mortality and RMNCAH inequalities, which was expected to occur during the SDG period based on the assumption that the spectacular progress achieved during the MDG period would continue unabated. Multiple threats, external and internal to the RMNCAH health community, must be addressed to safeguard the gains in RMNCAH and nutrition and to accelerate progress. Furthermore, a large gap between sub-Saharan Africa, especially West and Central Africa, and other parts of the world persists for many indicators, necessitating further prioritisation of this region.
30.
Liu, Xiaobo; Guo, Pi; Liang, Ying; Chen, Chuanwei; Sun, Jince; Wu, Haisheng; Su, Tianyun; Lai, Shengjie; Liu, Qiyong
Lessons from failure to success on malaria elimination in the Huai River Basin in China Journal Article
In: bmj, vol. 389, 2025.
Abstract | Links | BibTeX | Tags:
@article{liu2025lessons,
title = {Lessons from failure to success on malaria elimination in the Huai River Basin in China},
author = {Xiaobo Liu and Pi Guo and Ying Liang and Chuanwei Chen and Jince Sun and Haisheng Wu and Tianyun Su and Shengjie Lai and Qiyong Liu},
url = {https://doi.org/10.1136/bmj-2024-080658},
year = {2025},
date = {2025-01-01},
urldate = {2025-01-01},
journal = {bmj},
volume = {389},
publisher = {British Medical Journal Publishing Group},
abstract = {Malaria is still a significant public health threat. After generations of control efforts, China was certified as a malaria-free country by the World Health Organization in June 2021. Not without its challenges, China’s experience of eliminating malaria is informative for elimination strategies in other countries and regions.
The Huai River Basin (HRB) in central China was the epicentre of two epidemics in the 1960s and 1970s, accounting for 93.1% and 91.2% of total reported cases in China, respectively.5 A comprehensive control strategy focused on eliminating infection sources, supplemented by integrated mosquito control, was adopted, such that by 1987 most regions in the HRB had achieved “basic malaria elimination”—with incidence rates below 1/10 000.
Unfortunately, malaria resurged in the HRB in 2003 and peaked in 2006. At that time, 62.45% of China’s total cases (60 193 cases) were in the HRB.5 As a result, the government’s leadership in malaria control was re-enforced through the implementation of comprehensive measures, such as mass drug administration, case management,6 and sustainable vector management.7 Consequently, the incidence of malaria in the HRB decreased significantly. No indigenous malaria has occurred in the HRB since the end of 2012.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Malaria is still a significant public health threat. After generations of control efforts, China was certified as a malaria-free country by the World Health Organization in June 2021. Not without its challenges, China’s experience of eliminating malaria is informative for elimination strategies in other countries and regions.
The Huai River Basin (HRB) in central China was the epicentre of two epidemics in the 1960s and 1970s, accounting for 93.1% and 91.2% of total reported cases in China, respectively.5 A comprehensive control strategy focused on eliminating infection sources, supplemented by integrated mosquito control, was adopted, such that by 1987 most regions in the HRB had achieved “basic malaria elimination”—with incidence rates below 1/10 000.
Unfortunately, malaria resurged in the HRB in 2003 and peaked in 2006. At that time, 62.45% of China’s total cases (60 193 cases) were in the HRB.5 As a result, the government’s leadership in malaria control was re-enforced through the implementation of comprehensive measures, such as mass drug administration, case management,6 and sustainable vector management.7 Consequently, the incidence of malaria in the HRB decreased significantly. No indigenous malaria has occurred in the HRB since the end of 2012.
The Huai River Basin (HRB) in central China was the epicentre of two epidemics in the 1960s and 1970s, accounting for 93.1% and 91.2% of total reported cases in China, respectively.5 A comprehensive control strategy focused on eliminating infection sources, supplemented by integrated mosquito control, was adopted, such that by 1987 most regions in the HRB had achieved “basic malaria elimination”—with incidence rates below 1/10 000.
Unfortunately, malaria resurged in the HRB in 2003 and peaked in 2006. At that time, 62.45% of China’s total cases (60 193 cases) were in the HRB.5 As a result, the government’s leadership in malaria control was re-enforced through the implementation of comprehensive measures, such as mass drug administration, case management,6 and sustainable vector management.7 Consequently, the incidence of malaria in the HRB decreased significantly. No indigenous malaria has occurred in the HRB since the end of 2012.
31.
Liu, Qiyong; Wang, Yiguan; Liu, Xiaobo; Hay, Simon I; Lai, Shengjie
Stratified sustainable vector control strategies and measures for malaria control and elimination in China: a 70 year journey Journal Article
In: bmj, vol. 389, 2025.
Abstract | Links | BibTeX | Tags:
@article{liu2025stratified,
title = {Stratified sustainable vector control strategies and measures for malaria control and elimination in China: a 70 year journey},
author = {Qiyong Liu and Yiguan Wang and Xiaobo Liu and Simon I Hay and Shengjie Lai},
url = {https://doi.org/10.1136/bmj-2024-080656},
year = {2025},
date = {2025-01-01},
urldate = {2025-01-01},
journal = {bmj},
volume = {389},
publisher = {British Medical Journal Publishing Group},
abstract = {Malaria is a mosquito-borne infectious disease that significantly threatens global health. Considerable efforts and investments have led to a steady decline in incidence and mortality over recent decades. However, 249 million cases were reported from 85 countries and areas in 2022, resulting in 608 000 deaths.1 Notably, approximately 95% of these cases and deaths occurred in the African region. China has had a heavy disease burden of malaria for more than 3000 years, evidenced by the Chinese character for malaria—疟 or nüè—discovered on oracle bone and bronze inscriptions from between 1562 and 1066 BC.2 Chinese medicine has historically been used to treat people with malaria. However, in the 1940s, before the foundation of the People’s Republic of China, the burden of malaria was still immense, with an estimated 30 million annual cases, more than 90% of the population at risk, and a fatality rate of approximately 1%.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Malaria is a mosquito-borne infectious disease that significantly threatens global health. Considerable efforts and investments have led to a steady decline in incidence and mortality over recent decades. However, 249 million cases were reported from 85 countries and areas in 2022, resulting in 608 000 deaths.1 Notably, approximately 95% of these cases and deaths occurred in the African region. China has had a heavy disease burden of malaria for more than 3000 years, evidenced by the Chinese character for malaria—疟 or nüè—discovered on oracle bone and bronze inscriptions from between 1562 and 1066 BC.2 Chinese medicine has historically been used to treat people with malaria. However, in the 1940s, before the foundation of the People’s Republic of China, the burden of malaria was still immense, with an estimated 30 million annual cases, more than 90% of the population at risk, and a fatality rate of approximately 1%.
32.
Seidler, Valentin; Utazi, Edson C; Finaret, Amelia B; Luckeneder, Sebastian; Zens, Gregor; Bodarenko, Maksym; Smith, Abigail W; Bradley, Sarah EK; Tatem, Andrew J; Webb, Patrick
Subnational variations in the quality of household survey data in sub-Saharan Africa Journal Article
In: Nature Communications, vol. 16, no. 1, pp. 3771, 2025.
Abstract | Links | BibTeX | Tags:
@article{seidler2025subnational,
title = {Subnational variations in the quality of household survey data in sub-Saharan Africa},
author = {Valentin Seidler and Edson C Utazi and Amelia B Finaret and Sebastian Luckeneder and Gregor Zens and Maksym Bodarenko and Abigail W Smith and Sarah EK Bradley and Andrew J Tatem and Patrick Webb},
url = {https://doi.org/10.1038/s41467-025-58776-5},
year = {2025},
date = {2025-01-01},
urldate = {2025-01-01},
journal = {Nature Communications},
volume = {16},
number = {1},
pages = {3771},
publisher = {Nature Publishing Group UK London},
abstract = {Nationally representative household surveys collect geocoded data that are vital to tackling health and other development challenges in sub-Saharan Africa. Scholars and practitioners generally assume uniform data quality but subnational variation of errors in household data has never been investigated at high spatial resolution. Here, we explore within-country variation in the quality of most recent household surveys for 35 African countries at 5 × 5 km resolution and district levels. Findings show a striking heterogeneity in the subnational distribution of sampling and measurement errors. Data quality degrades with greater distance from settlements, and missing data as well as imprecision of estimates add to quality problems that can result in vulnerable remote populations receiving less than optimal services and needed resources. Our easy-to-access geospatial estimates of survey data quality highlight the need to invest in better targeting of household surveys in remote areas.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Nationally representative household surveys collect geocoded data that are vital to tackling health and other development challenges in sub-Saharan Africa. Scholars and practitioners generally assume uniform data quality but subnational variation of errors in household data has never been investigated at high spatial resolution. Here, we explore within-country variation in the quality of most recent household surveys for 35 African countries at 5 × 5 km resolution and district levels. Findings show a striking heterogeneity in the subnational distribution of sampling and measurement errors. Data quality degrades with greater distance from settlements, and missing data as well as imprecision of estimates add to quality problems that can result in vulnerable remote populations receiving less than optimal services and needed resources. Our easy-to-access geospatial estimates of survey data quality highlight the need to invest in better targeting of household surveys in remote areas.
33.
Chamberlain, Heather R; Pollard, Derek; Winters, Anna; Renn, Silvia; Borkovska, Olena; Musuka, Chisenga Abel; Membele, Garikai; Lazar, Attila N; Tatem, Andrew J
In: International Journal of Health Geographics, vol. 24, no. 1, pp. 13, 2025.
Abstract | Links | BibTeX | Tags:
@article{chamberlain2025assessing,
title = {Assessing the impact of building footprint dataset choice for health programme planning: a case study of indoor residual spraying (IRS) in Zambia},
author = {Heather R Chamberlain and Derek Pollard and Anna Winters and Silvia Renn and Olena Borkovska and Chisenga Abel Musuka and Garikai Membele and Attila N Lazar and Andrew J Tatem},
url = {https://doi.org/10.1186/s12942-025-00398-7},
year = {2025},
date = {2025-01-01},
urldate = {2025-01-01},
journal = {International Journal of Health Geographics},
volume = {24},
number = {1},
pages = {13},
publisher = {Springer},
abstract = {The increasing availability globally of building footprint datasets has brought new opportunities to support a geographic approach to health programme planning. This is particularly acute in settings with high disease burdens but limited geospatial data available to support targeted planning. The comparability of building footprint datasets has recently started to be explored, but the impact of utilising a particular dataset in analyses to support decision making for health programme planning has not been studied. In this study, we quantify the impact of utilising four different building footprint datasets in analyses to support health programme planning, with an example of malaria vector control initiatives in Zambia.
Using the example of planning indoor residual spraying (IRS) campaigns in Zambia, we identify priority locations for deployment of this intervention based on criteria related to the area, proximity and counts of building footprints per settlement. We apply the same criteria to four different building footprint datasets and quantify the count and geographic variability in the priority settlements that are identified.
We show that nationally the count of potential priority settlements for IRS varies by over 230% with different building footprint datasets, considering a minimum threshold of 25 sprayable buildings per settlement. Differences are most pronounced for rural settlements, indicating that the choice of dataset may bias the selection to include or exclude settlements, and consequently population groups, in some areas.
The results of this study show that the choice of building footprint dataset can have a considerable impact on the potential settlements identified for IRS, in terms of (i) their location and count, and (ii) the count of building footprints within priority settlements. The choice of dataset potentially has substantial implications for campaign planning, implementation and coverage assessment. Given the magnitude of the differences observed, further work should more broadly assess the sensitivity of health programme planning metrics to different building footprint datasets, and across a range of geographic contexts and health campaign types.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The increasing availability globally of building footprint datasets has brought new opportunities to support a geographic approach to health programme planning. This is particularly acute in settings with high disease burdens but limited geospatial data available to support targeted planning. The comparability of building footprint datasets has recently started to be explored, but the impact of utilising a particular dataset in analyses to support decision making for health programme planning has not been studied. In this study, we quantify the impact of utilising four different building footprint datasets in analyses to support health programme planning, with an example of malaria vector control initiatives in Zambia.
Using the example of planning indoor residual spraying (IRS) campaigns in Zambia, we identify priority locations for deployment of this intervention based on criteria related to the area, proximity and counts of building footprints per settlement. We apply the same criteria to four different building footprint datasets and quantify the count and geographic variability in the priority settlements that are identified.
We show that nationally the count of potential priority settlements for IRS varies by over 230% with different building footprint datasets, considering a minimum threshold of 25 sprayable buildings per settlement. Differences are most pronounced for rural settlements, indicating that the choice of dataset may bias the selection to include or exclude settlements, and consequently population groups, in some areas.
The results of this study show that the choice of building footprint dataset can have a considerable impact on the potential settlements identified for IRS, in terms of (i) their location and count, and (ii) the count of building footprints within priority settlements. The choice of dataset potentially has substantial implications for campaign planning, implementation and coverage assessment. Given the magnitude of the differences observed, further work should more broadly assess the sensitivity of health programme planning metrics to different building footprint datasets, and across a range of geographic contexts and health campaign types.
Using the example of planning indoor residual spraying (IRS) campaigns in Zambia, we identify priority locations for deployment of this intervention based on criteria related to the area, proximity and counts of building footprints per settlement. We apply the same criteria to four different building footprint datasets and quantify the count and geographic variability in the priority settlements that are identified.
We show that nationally the count of potential priority settlements for IRS varies by over 230% with different building footprint datasets, considering a minimum threshold of 25 sprayable buildings per settlement. Differences are most pronounced for rural settlements, indicating that the choice of dataset may bias the selection to include or exclude settlements, and consequently population groups, in some areas.
The results of this study show that the choice of building footprint dataset can have a considerable impact on the potential settlements identified for IRS, in terms of (i) their location and count, and (ii) the count of building footprints within priority settlements. The choice of dataset potentially has substantial implications for campaign planning, implementation and coverage assessment. Given the magnitude of the differences observed, further work should more broadly assess the sensitivity of health programme planning metrics to different building footprint datasets, and across a range of geographic contexts and health campaign types.
34.
Nnanatu, Chibuzor Christopher; Bonnie, Amy; Joseph, Josiah; Yankey, Ortis; Cihan, Duygu; Gadiaga, Assane; Voepel, Hal; Abbott, Thomas; Chamberlain, Heather R; Tia, Mercedita; others,
Estimating small area population from health intervention campaign surveys and partially observed settlement data Journal Article
In: Nature Communications, vol. 16, no. 1, pp. 4951, 2025.
Abstract | Links | BibTeX | Tags:
@article{nnanatu2025estimating,
title = {Estimating small area population from health intervention campaign surveys and partially observed settlement data},
author = {Chibuzor Christopher Nnanatu and Amy Bonnie and Josiah Joseph and Ortis Yankey and Duygu Cihan and Assane Gadiaga and Hal Voepel and Thomas Abbott and Heather R Chamberlain and Mercedita Tia and others},
url = {https://doi.org/10.1038/s41467-025-59862-4},
year = {2025},
date = {2025-01-01},
urldate = {2025-01-01},
journal = {Nature Communications},
volume = {16},
number = {1},
pages = {4951},
publisher = {Nature Publishing Group UK London},
abstract = {Effective governance requires timely and reliable small area population counts. Geospatial modelling approaches which utilise bespoke microcensus surveys and satellite-derived settlement maps and other spatial datasets have been developed to fill population data gaps in countries where censuses are outdated and incomplete. However, logistics and costs of microcensus surveys and tree canopy or cloud cover obscuring settlements in satellite images limit its wider applications in tropical rural settings. Here, we present a two-step Bayesian hierarchical modelling approach that can integrate routinely collected health intervention campaign data and partially observed settlement data to produce reliable small area population estimates. Reductions in relative error rates were 32–73% in a simulation study, and ~32% when applied to malaria survey data in Papua New Guinea. The results highlight the value of demographic data routinely collected through health intervention campaigns or household surveys for improving small area population estimates, and how biases introduced by satellite data limitations can be overcome.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Effective governance requires timely and reliable small area population counts. Geospatial modelling approaches which utilise bespoke microcensus surveys and satellite-derived settlement maps and other spatial datasets have been developed to fill population data gaps in countries where censuses are outdated and incomplete. However, logistics and costs of microcensus surveys and tree canopy or cloud cover obscuring settlements in satellite images limit its wider applications in tropical rural settings. Here, we present a two-step Bayesian hierarchical modelling approach that can integrate routinely collected health intervention campaign data and partially observed settlement data to produce reliable small area population estimates. Reductions in relative error rates were 32–73% in a simulation study, and ~32% when applied to malaria survey data in Papua New Guinea. The results highlight the value of demographic data routinely collected through health intervention campaigns or household surveys for improving small area population estimates, and how biases introduced by satellite data limitations can be overcome.
35.
Wariri, Oghenebrume; Utazi, Chigozie Edson; Okomo, Uduak; Dotse-Gborgbortsi, Winfred; Sogur, Malick; Fofana, Sidat; Murray, Kris A.; Grundy, Chris; Kampmann, Beate
Multi-level determinants of timely routine childhood vaccinations in The Gambia: Findings from a nationwide analysis Journal Article
In: Vaccine, vol. 43, 2025.
Abstract | Links | BibTeX | Tags:
@article{nokey,
title = {Multi-level determinants of timely routine childhood vaccinations in The Gambia: Findings from a nationwide analysis},
author = {Oghenebrume Wariri and Chigozie Edson Utazi and Uduak Okomo and Winfred Dotse-Gborgbortsi and Malick Sogur and Sidat Fofana and Kris A. Murray and Chris Grundy and Beate Kampmann },
url = {https://doi.org/10.1016/j.vaccine.2024.126500},
year = {2025},
date = {2025-01-01},
journal = {Vaccine},
volume = {43},
abstract = {Achieving the ambitious goals of the Immunisation Agenda 2030 (IA2030) requires a deeper understanding of factors influencing under-vaccination, including timely vaccination. This study investigates the demand- and supply-side determinants influencing the timely uptake of key childhood vaccines scheduled throughout the first year of life in The Gambia.
We used two nationally-representative datasets: the 2019–20 Gambian Demographic and Health Survey and the 2019 national immunisation facility mapping. Using Bayesian multi-level binary logistic regression models, we identified key factors significantly associated with timely vaccination for five key vaccines: birth dose of hepatitis-B (HepB0), first, second, and third doses of the pentavalent vaccine (Penta1, Penta2, Penta3), and first-dose of measles-containing vaccine (MCV1) in children
We found that demand-side factors, such as ethnicity, household wealth status, maternal education, maternal parity, and the duration of the household's residency in its current location, were the most common drivers of timely childhood vaccination. However, supply-side factors such as travel time to the nearest immunisation clinic, availability of cold-storage and staffing numbers in the nearest immunisation clinic were also significant determinants. Furthermore, the determinants varied across specific vaccines and the timing of doses. For example, delivery in a health facility (aOR = 1.58, 95 %CI: 1.02–2.53), living less than 30 min (aOR = 2.11, 95 %CI: 1.2–8.84) and living between 30 and 60 min (aOR = 3.68, 95 %CI: 1.1–14.99) from a fixed-immunisation clinic was associated with timely HepB0, a time-sensitive vaccine that must be administered within 24 h of birth. On the other hand, children who received Penta1 and Penta2 on time were three- to five-fold more likely to receive subsequent doses on time (Penta2 and Penta3, respectively). Finally, proximity to an immunisation facility with functional vaccine cold-storage was a significant supply-side determinant of timely MCV1 (aOR = 1.4, 95 %CI: 1.09–1.99).
These findings provide valuable insights for programme managers and policymakers. By prioritising interventions and allocating scarce resources based on these identified determinants, they can maximize their impact and ensure children in The Gambia receive timely vaccinations throughout their first year of life, contributing to IA2030 goals.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Achieving the ambitious goals of the Immunisation Agenda 2030 (IA2030) requires a deeper understanding of factors influencing under-vaccination, including timely vaccination. This study investigates the demand- and supply-side determinants influencing the timely uptake of key childhood vaccines scheduled throughout the first year of life in The Gambia.
We used two nationally-representative datasets: the 2019–20 Gambian Demographic and Health Survey and the 2019 national immunisation facility mapping. Using Bayesian multi-level binary logistic regression models, we identified key factors significantly associated with timely vaccination for five key vaccines: birth dose of hepatitis-B (HepB0), first, second, and third doses of the pentavalent vaccine (Penta1, Penta2, Penta3), and first-dose of measles-containing vaccine (MCV1) in children
We found that demand-side factors, such as ethnicity, household wealth status, maternal education, maternal parity, and the duration of the household's residency in its current location, were the most common drivers of timely childhood vaccination. However, supply-side factors such as travel time to the nearest immunisation clinic, availability of cold-storage and staffing numbers in the nearest immunisation clinic were also significant determinants. Furthermore, the determinants varied across specific vaccines and the timing of doses. For example, delivery in a health facility (aOR = 1.58, 95 %CI: 1.02–2.53), living less than 30 min (aOR = 2.11, 95 %CI: 1.2–8.84) and living between 30 and 60 min (aOR = 3.68, 95 %CI: 1.1–14.99) from a fixed-immunisation clinic was associated with timely HepB0, a time-sensitive vaccine that must be administered within 24 h of birth. On the other hand, children who received Penta1 and Penta2 on time were three- to five-fold more likely to receive subsequent doses on time (Penta2 and Penta3, respectively). Finally, proximity to an immunisation facility with functional vaccine cold-storage was a significant supply-side determinant of timely MCV1 (aOR = 1.4, 95 %CI: 1.09–1.99).
These findings provide valuable insights for programme managers and policymakers. By prioritising interventions and allocating scarce resources based on these identified determinants, they can maximize their impact and ensure children in The Gambia receive timely vaccinations throughout their first year of life, contributing to IA2030 goals.
We used two nationally-representative datasets: the 2019–20 Gambian Demographic and Health Survey and the 2019 national immunisation facility mapping. Using Bayesian multi-level binary logistic regression models, we identified key factors significantly associated with timely vaccination for five key vaccines: birth dose of hepatitis-B (HepB0), first, second, and third doses of the pentavalent vaccine (Penta1, Penta2, Penta3), and first-dose of measles-containing vaccine (MCV1) in children
We found that demand-side factors, such as ethnicity, household wealth status, maternal education, maternal parity, and the duration of the household's residency in its current location, were the most common drivers of timely childhood vaccination. However, supply-side factors such as travel time to the nearest immunisation clinic, availability of cold-storage and staffing numbers in the nearest immunisation clinic were also significant determinants. Furthermore, the determinants varied across specific vaccines and the timing of doses. For example, delivery in a health facility (aOR = 1.58, 95 %CI: 1.02–2.53), living less than 30 min (aOR = 2.11, 95 %CI: 1.2–8.84) and living between 30 and 60 min (aOR = 3.68, 95 %CI: 1.1–14.99) from a fixed-immunisation clinic was associated with timely HepB0, a time-sensitive vaccine that must be administered within 24 h of birth. On the other hand, children who received Penta1 and Penta2 on time were three- to five-fold more likely to receive subsequent doses on time (Penta2 and Penta3, respectively). Finally, proximity to an immunisation facility with functional vaccine cold-storage was a significant supply-side determinant of timely MCV1 (aOR = 1.4, 95 %CI: 1.09–1.99).
These findings provide valuable insights for programme managers and policymakers. By prioritising interventions and allocating scarce resources based on these identified determinants, they can maximize their impact and ensure children in The Gambia receive timely vaccinations throughout their first year of life, contributing to IA2030 goals.
36.
Kostandova, Natalya; Schluth, Catherine; Arambepola, Rohan; Atuhaire, Fatumah; Bérubé, Sophie; Chin, Taylor; Cleary, Eimear; Cortes-Azuero, Oscar; García-Carreras, Bernardo; Grantz, Kyra H.; Hitchings, Matt D. T.; Huang, Angkana T.; Kishore, Nishant; Lai, Shengjie; Larsen, Soren L.; Loisate, Stacie; Martinez, Pamela; Meredith, Hannah R.; Purbey, Ritika; Ramiadantsoa, Tanjona; Read, Jonathan; Rice, Benjamin L.; Rosman, Lori; Ruktanonchai, Nick; Salje, Henrik; Schaber, Kathryn L.; Tatem, Andrew J.; Wang, Jasmine; Cummings, Derek A. T.; Wesolowski, Amy
A systematic review of using population-level human mobility data to understand SARS-CoV-2 transmission Journal Article
In: Nature Communications, vol. 15, no. 10504, 2024.
Abstract | Links | BibTeX | Tags:
@article{nokey,
title = {A systematic review of using population-level human mobility data to understand SARS-CoV-2 transmission},
author = {Natalya Kostandova and Catherine Schluth and Rohan Arambepola and Fatumah Atuhaire and Sophie Bérubé and Taylor Chin and Eimear Cleary and Oscar Cortes-Azuero and Bernardo García-Carreras and Kyra H. Grantz and Matt D. T. Hitchings and Angkana T. Huang and Nishant Kishore and Shengjie Lai and Soren L. Larsen and Stacie Loisate and Pamela Martinez and Hannah R. Meredith and Ritika Purbey and Tanjona Ramiadantsoa and Jonathan Read and Benjamin L. Rice and Lori Rosman and Nick Ruktanonchai and Henrik Salje and Kathryn L. Schaber and Andrew J. Tatem and Jasmine Wang and Derek A. T. Cummings and Amy Wesolowski },
url = {https://doi.org/10.1038/s41467-024-54895-7},
year = {2024},
date = {2024-12-03},
journal = {Nature Communications},
volume = {15},
number = {10504},
abstract = {The emergence of SARS-CoV-2 into a highly susceptible global population was primarily driven by human mobility-induced introduction events. Especially in the early stages, understanding mobility was vital to mitigating the pandemic prior to widespread vaccine availability. We conducted a systematic review of studies published from January 1, 2020, to May 9, 2021, that used population-level human mobility data to understand SARS-CoV-2 transmission. Of the 5505 papers with abstracts screened, 232 were included in the analysis. These papers focused on a range of specific questions but were dominated by analyses focusing on the USA and China. The majority included mobile phone data, followed by Google Community Mobility Reports, and few included any adjustments to account for potential biases in population sampling processes. There was no clear relationship between methods used to integrate mobility and SARS-CoV-2 data and goals of analysis. When considering papers focused only on the estimation of the effective reproductive number within the US, there was no clear relationship identified between this measure and changes in mobility patterns. Our findings underscore the need for standardized, systematic ways to identify the source of mobility data, select an appropriate approach to using it in analysis, and reporting.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The emergence of SARS-CoV-2 into a highly susceptible global population was primarily driven by human mobility-induced introduction events. Especially in the early stages, understanding mobility was vital to mitigating the pandemic prior to widespread vaccine availability. We conducted a systematic review of studies published from January 1, 2020, to May 9, 2021, that used population-level human mobility data to understand SARS-CoV-2 transmission. Of the 5505 papers with abstracts screened, 232 were included in the analysis. These papers focused on a range of specific questions but were dominated by analyses focusing on the USA and China. The majority included mobile phone data, followed by Google Community Mobility Reports, and few included any adjustments to account for potential biases in population sampling processes. There was no clear relationship between methods used to integrate mobility and SARS-CoV-2 data and goals of analysis. When considering papers focused only on the estimation of the effective reproductive number within the US, there was no clear relationship identified between this measure and changes in mobility patterns. Our findings underscore the need for standardized, systematic ways to identify the source of mobility data, select an appropriate approach to using it in analysis, and reporting.
37.
Tian, Ya; Zhang, Junze; Li, Zonghan; Wu, Kai; Cao, Min; Lin, Jian; Pradhan, Prajal; Lai, Shengjie; Meng, Jia; Fu, Bojie; Chen, Min; Lin, Hui
Trade-offs among human, animal, and environmental health hinder the uniform progress of global One Health Journal Article
In: iScience, vol. 27, iss. 12, 2024.
Abstract | Links | BibTeX | Tags:
@article{nokey,
title = {Trade-offs among human, animal, and environmental health hinder the uniform progress of global One Health},
author = {Tian, Ya and Zhang, Junze and Li, Zonghan and Wu, Kai and Cao, Min and Lin, Jian and Pradhan, Prajal and Lai, Shengjie and Meng, Jia and Fu, Bojie and Chen, Min and Lin, Hui },
url = {https://doi.org/10.1016/j.isci.2024.111357},
doi = {10.1016/j.isci.2024.111357 },
year = {2024},
date = {2024-11-22},
journal = {iScience},
volume = {27},
issue = {12},
abstract = {The One Health (OH) approach, integrating aspects of human, animal, and environmental health, still lacks robustly quantified insights into its complex relationships. To fill this knowledge gap, we devised a comprehensive assessment scheme for OH to assess its progress, synergies, trade-offs, and priority targets. From 2000 to 2020, we find evidence for global progress toward OH, albeit uneven, with its average score rising from 61.6 to 65.5, driven primarily by better human health although environmental health lags. Despite synergies prevalent within and between the three health dimensions, over half of the world’s countries, mainly low-income ones, still incur substantial trade-offs impeding OH’s advancement, especially between animal and environmental health. Our in-depth analysis of synergy and trade-off networks reveals that maternal, newborn, and child health are critical synergistic targets, whereas biodiversity and land resources dominate trade-offs. We provide key information for the synergetic and uniform development of global OH and policymaking.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The One Health (OH) approach, integrating aspects of human, animal, and environmental health, still lacks robustly quantified insights into its complex relationships. To fill this knowledge gap, we devised a comprehensive assessment scheme for OH to assess its progress, synergies, trade-offs, and priority targets. From 2000 to 2020, we find evidence for global progress toward OH, albeit uneven, with its average score rising from 61.6 to 65.5, driven primarily by better human health although environmental health lags. Despite synergies prevalent within and between the three health dimensions, over half of the world’s countries, mainly low-income ones, still incur substantial trade-offs impeding OH’s advancement, especially between animal and environmental health. Our in-depth analysis of synergy and trade-off networks reveals that maternal, newborn, and child health are critical synergistic targets, whereas biodiversity and land resources dominate trade-offs. We provide key information for the synergetic and uniform development of global OH and policymaking.
38.
Utazi, C. Edson; Olowe, Iyanuloluwa D.; Chan, H. M. Theophilus; Dotse-Gborgbortsi, Winfred; Wagai, John; Umar, Jamila A.; Etamesor, Sulaiman; Atuhaire, Brian; Fafunmi, Biyi; Crawford, Jessica; Adeniran, Adeyemi; Tatem, Andrew J.
In: Vaccines, vol. 12, no. 1299, 2024.
Abstract | Links | BibTeX | Tags:
@article{nokey,
title = {Geospatial Variation in Vaccination Coverage and Zero-Dose Prevalence at the District, Ward and Health Facility Levels Before and After a Measles Vaccination Campaign in Nigeria},
author = {C. Edson Utazi and Iyanuloluwa D. Olowe and H. M. Theophilus Chan and Winfred Dotse-Gborgbortsi and John Wagai and Jamila A. Umar and Sulaiman Etamesor and Brian Atuhaire and Biyi Fafunmi and Jessica Crawford and Adeyemi Adeniran and Andrew J. Tatem},
url = {https://doi.org/10.3390/vaccines12121299},
year = {2024},
date = {2024-11-21},
journal = {Vaccines},
volume = {12},
number = {1299},
abstract = {Many measles endemic countries with suboptimal coverage levels still rely on vaccination campaigns to fill immunity gaps and boost control efforts. Depending on local epidemiological patterns, national or targeted campaigns are implemented, following which post-campaign coverage surveys (PCCSs) are conducted to evaluate their performance, particularly in terms of reaching previously unvaccinated children. Due to limited resources, PCCS surveys are designed to be representative at coarse spatial scales, often masking important heterogeneities in coverage that could enhance the identification of areas of poor performance for follow-up via routine immunization strategies. Here, we undertake geospatial analyses of the 2021 measles PCCS in Nigeria to map indicators of coverage measuring the individual and combined performance of the campaign and routine immunization (RI) at 1 × 1 km resolution and the ward and district levels in 13 states. Using additional geospatial datasets, we also produced estimates of numbers of unvaccinated children during the campaign and numbers of measles-containing vaccine (MCV) zero-dose children before and after the campaign at these levels and within health facility catchment areas. Our study revealed that although the campaign reduced the numbers of MCV zero-dose children in all the districts, areas of suboptimal campaign and RI performance with considerable numbers of zero-dose children remained. Our analyses further identified wards and health facility catchment areas with higher numbers of unvaccinated children within these areas. Our outputs provide a robust evidence base to plan and implement follow-up RI strategies and to guide future campaigns at flexible and operationally relevant spatial scales.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Many measles endemic countries with suboptimal coverage levels still rely on vaccination campaigns to fill immunity gaps and boost control efforts. Depending on local epidemiological patterns, national or targeted campaigns are implemented, following which post-campaign coverage surveys (PCCSs) are conducted to evaluate their performance, particularly in terms of reaching previously unvaccinated children. Due to limited resources, PCCS surveys are designed to be representative at coarse spatial scales, often masking important heterogeneities in coverage that could enhance the identification of areas of poor performance for follow-up via routine immunization strategies. Here, we undertake geospatial analyses of the 2021 measles PCCS in Nigeria to map indicators of coverage measuring the individual and combined performance of the campaign and routine immunization (RI) at 1 × 1 km resolution and the ward and district levels in 13 states. Using additional geospatial datasets, we also produced estimates of numbers of unvaccinated children during the campaign and numbers of measles-containing vaccine (MCV) zero-dose children before and after the campaign at these levels and within health facility catchment areas. Our study revealed that although the campaign reduced the numbers of MCV zero-dose children in all the districts, areas of suboptimal campaign and RI performance with considerable numbers of zero-dose children remained. Our analyses further identified wards and health facility catchment areas with higher numbers of unvaccinated children within these areas. Our outputs provide a robust evidence base to plan and implement follow-up RI strategies and to guide future campaigns at flexible and operationally relevant spatial scales.
39.
Yankey, Ortis; Utazi, Chigozie E.; Nnanatu, Christopher C.; Gadiaga, Assane N.; Abbot, Thomas; Lazar, Attila N.; Tatem, Andrew J.
Disaggregating census data for population mapping using a Bayesian Additive Regression Tree model Journal Article
In: Applied Geography, vol. 174, 2024.
Abstract | Links | BibTeX | Tags:
@article{nokey,
title = {Disaggregating census data for population mapping using a Bayesian Additive Regression Tree model},
author = {Ortis Yankey and Chigozie E. Utazi and Christopher C. Nnanatu and Assane N. Gadiaga and Thomas Abbot and Attila N. Lazar and Andrew J. Tatem},
url = {https://doi.org/10.1016/j.apgeog.2024.103416},
year = {2024},
date = {2024-09-14},
journal = {Applied Geography},
volume = {174},
abstract = {Population data is crucial for policy decisions, but fine-scale population numbers are often lacking due to the challenge of sharing sensitive data. Different approaches, such as the use of the Random Forest (RF) model, have been used to disaggregate census data from higher administrative units to small area scales. A major limitation of the RF model is its inability to quantify the uncertainties associated with the predicted populations, which can be important for policy decisions. In this study, we applied a Bayesian Additive Regression Tree (BART) model for population disaggregation and compared the result with a RF model using both simulated data and the 2021 census data for Ghana. The BART model consistently outperforms the RF model in out-of-sample predictions for all metrics, such as bias, mean squared error (MSE), and root mean squared error (RMSE). The BART model also addresses the limitations of the RF model by providing uncertainty estimates around the predicted population, which is often lacking with the RF model. Overall, the study demonstrates the superiority of the BART model over the RF model in disaggregating population data and highlights its potential for gridded population estimates.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Population data is crucial for policy decisions, but fine-scale population numbers are often lacking due to the challenge of sharing sensitive data. Different approaches, such as the use of the Random Forest (RF) model, have been used to disaggregate census data from higher administrative units to small area scales. A major limitation of the RF model is its inability to quantify the uncertainties associated with the predicted populations, which can be important for policy decisions. In this study, we applied a Bayesian Additive Regression Tree (BART) model for population disaggregation and compared the result with a RF model using both simulated data and the 2021 census data for Ghana. The BART model consistently outperforms the RF model in out-of-sample predictions for all metrics, such as bias, mean squared error (MSE), and root mean squared error (RMSE). The BART model also addresses the limitations of the RF model by providing uncertainty estimates around the predicted population, which is often lacking with the RF model. Overall, the study demonstrates the superiority of the BART model over the RF model in disaggregating population data and highlights its potential for gridded population estimates.
40.
Duan, Qianwen; Steele, Jessica; Cheng, Zhifeng; Cleary, Eimear; Ruktanonchai, Nick; Voepel, Hal; O'Riordan, Tim; Tatem, Andrew J.; Sorichetta, Alessandro; Lai, Shengjie; Eigenbrod, Felix
Identifying counter-urbanisation using Facebook's user count data Journal Article
In: Habitat International, vol. 150, 2024.
Abstract | Links | BibTeX | Tags:
@article{nokey,
title = {Identifying counter-urbanisation using Facebook's user count data},
author = {Qianwen Duan and Jessica Steele and Zhifeng Cheng and Eimear Cleary and Nick Ruktanonchai and Hal Voepel and Tim O'Riordan and Andrew J. Tatem and Alessandro Sorichetta and Shengjie Lai and Felix Eigenbrod},
url = {https://doi.org/10.1016/j.habitatint.2024.103113},
doi = {10.1016/j.habitatint.2024.103113},
year = {2024},
date = {2024-06-04},
journal = {Habitat International},
volume = {150},
abstract = {Identifying the growing widespread phenomenon of counter-urbanisation, where people relocate from urban centres to rural areas, is essential for understanding the social and ecological consequences of the associated changes. However, its nuanced dynamics and complex characteristics pose challenges for quantitative analysis. Here, we used near real-time Facebook user count data for Belgium and Thailand, with missing data imputed, and applied the Seasonal-Trend decomposition using Loess (STL) model to capture subtle urban and rural population dynamics and assess counter-urbanisation. We identified counter-urbanisation in both Belgium and Thailand, evidenced by increases of 1.80% and 2.14% in rural residents (night-time user counts) and decreases of 3.08% and 5.04% in urban centre night-time user counts from March 2020 to May 2022, respectively. However, the counter-urbanisation in Thailand appears to be transitory, with rural users beginning to decline during both day and night as COVID-19 restrictions were lifted. By contrast, in Belgium, at the country level, there is as yet no evidence of a return to urban residences, though daytime numbers in rural areas are decreasing and in urban centres are increasing, suggesting an increase in commuting post-pandemic. These variation characteristics observed both between Belgium and Thailand and between day and night, extend the current understanding of counter-urbanisation. The use of novel social media data provides an effective quantitative perspective to comprehend counter-urbanisation in different settings.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Identifying the growing widespread phenomenon of counter-urbanisation, where people relocate from urban centres to rural areas, is essential for understanding the social and ecological consequences of the associated changes. However, its nuanced dynamics and complex characteristics pose challenges for quantitative analysis. Here, we used near real-time Facebook user count data for Belgium and Thailand, with missing data imputed, and applied the Seasonal-Trend decomposition using Loess (STL) model to capture subtle urban and rural population dynamics and assess counter-urbanisation. We identified counter-urbanisation in both Belgium and Thailand, evidenced by increases of 1.80% and 2.14% in rural residents (night-time user counts) and decreases of 3.08% and 5.04% in urban centre night-time user counts from March 2020 to May 2022, respectively. However, the counter-urbanisation in Thailand appears to be transitory, with rural users beginning to decline during both day and night as COVID-19 restrictions were lifted. By contrast, in Belgium, at the country level, there is as yet no evidence of a return to urban residences, though daytime numbers in rural areas are decreasing and in urban centres are increasing, suggesting an increase in commuting post-pandemic. These variation characteristics observed both between Belgium and Thailand and between day and night, extend the current understanding of counter-urbanisation. The use of novel social media data provides an effective quantitative perspective to comprehend counter-urbanisation in different settings.
