Use of parametric statistical models can be a solution to reduce the follow-up period time requir... more Use of parametric statistical models can be a solution to reduce the follow-up period time required to estimate long-term survival. Mould and Boag were the first to use the lognormal model. Competing risks methodology seems more suitable when a particular event type is of interest than classical survival analysis. The objective was to evaluate the ability of the Jeong and Fine model to predict long-term cumulative incidence. Survival data recorded by Institut Curie (Paris) from 4761 breast cancer patients treated and followed between 1981 and 2013 were used. Long-term cumulative incidence rates predicted by the model using short-term follow-up data were compared to non-parametric estimation using complete follow-up data. 20-or 25-year cumulative incidence rates for loco-regional recurrence and distant metastasis predicted by the model using a maximum of 10 years of follow-up data had a maximum difference of around 6 % compared to nonparametric estimation. Prediction rates were underestimated for the third and composite event (contralateral or second cancer or death). Predictive ability of Jeong and Fine model on breast cancer data was generally good considering the short follow-up period time used for the estimation especially when a proportion of patient did not experience loco-regional recurrence or distant metastasis.
BackgroundThe exposure to parasites may influence the immune response to vaccines in endemic Afri... more BackgroundThe exposure to parasites may influence the immune response to vaccines in endemic African countries. In this study, we aimed to assess the association between helminth exposure to the most prevalent parasitic infections, schistosomiasis, soil transmitted helminths infection and filariasis, and the Ebola virus glycoprotein (EBOV GP) antibody concentration in response to vaccination with the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen in African and European participants using samples obtained from three international clinical trials.Methods/Principal FindingsWe conducted a study in a subset of participants in the EBL2001, EBL2002 and EBL3001 clinical trials that evaluated the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen against EVD in children, adolescents and adults from the United Kingdom, France, Burkina Faso, Cote d’Ivoire, Kenya, Uganda and Sierra Leone. Immune markers of helminth exposure at baseline were evaluated by ELISA with three commercial kits which detect IgG antibodi...
Background: In April 2016, Burkina Faso began free healthcare for children aged from 0 to 5 years... more Background: In April 2016, Burkina Faso began free healthcare for children aged from 0 to 5 years. However, its implementation faces challenges, and the goal of this study is to estimate the fees paid for this child care and to determine the causes of these direct payments. Methods: Data gathering involved 807 children aged from 0 to 5 years who had contact with the public healthcare system. The estimation of the determinants of out-of-pocket health payments involved the application of a two-part regression model. Results: About 31% of the children made out-of-pocket payments for healthcare (an average of 3407.77 CFA francs per case of illness). Of these, 96% paid for medicines and 24% paid for consultations. The first model showed that out-of-pocket payments were positively associated with hospitalization, urban area of residence, and severity of illness, were made in the East-Central and North-Central regions, and were negatively associated with the 7 to 23 month age range. The se...
Objective: to analyse the pandemic after one year in terms of the evolution of morbidity and mort... more Objective: to analyse the pandemic after one year in terms of the evolution of morbidity and mortality and factors that may contribute to this evolutionDesign: This is a secondary analysis of data gathered to respond to the COVID-19 pandemic. The number of cases, incidence rate, cumulative incidence rate, number of deaths, case fatality rate and their trends were analysed during the first year of the pandemic. Testing and other public health measures were also described according to the information available.Settings: The 15 States members of the Economic Community of West African States (ECOWAS) were considered.Results: As of 31st March 2021, the ECOWAS region reported 429,760 COVID-19 cases and 5,620 deaths. In the first year, 1,110.75 persons were infected per million, while 1.31% of the confirmed patients died. The ECOWAS region represents 30% of the African population. One year after the start of COVID-19 in ECOWAS, this region reported 10% of the cases and 10% of the deaths in...
Background: While maternal mortality has declined globally, it remains highest in low-income coun... more Background: While maternal mortality has declined globally, it remains highest in low-income countries. High-quality antenatal care (ANC) can control or decrease pregnancy-related complications for mothers and newborns. The implementation of performance-based financing (PBF) schemes in Sub-Saharan Africa to improve primary healthcare provision commonly includes mechanisms targeting ANC service quality. In this study, we examine changes in ANC provision produced by the introduction of a PBF scheme in rural Burkina Faso.Methods: This study followed a quasi-experimental design with two data collection points comparing effects on ANC service quality between primary health facilities across intervention and control districts based on difference-in-differences estimates. Outcome variables were defined using data on structural and process quality of care reflecting key clinical aspects of ANC provision (i.e. screening, prevention) for two different client groups (i.e. first ANC visits, fol...
The American Journal of Tropical Medicine and Hygiene
To reduce child mortality in children younger than 5 years, Burkina Faso has been offering free c... more To reduce child mortality in children younger than 5 years, Burkina Faso has been offering free care to this population of children since 2016. The free care program is aligned with the Integrated Management of Childhood Illness (IMCI) guidelines. Given that the number of studies that evaluated the competence of health-care workers (HCWs) during the free care program was limited, we assessed the adherence level of HCWs to the IMCI guidelines in the context of free care. This was a secondary data analysis. Data were obtained from a cross-sectional study conducted from July to September 2020 in 40 primary health-care centers and two district hospitals in the Hauts-Bassins region in Burkina Faso. Our analysis included 419 children younger than 5 years old who were consulted according to IMCI guidelines. Data were collected through direct observation using a checklist. The overall score of adherence of HCWs to IMCI guidelines was 57.8% (95% CI, 42.6–73.0). The mean adherence score of th...
Background The Integrated eDiagnosis Approach (IeDA), centred on an electronic Clinical Decision ... more Background The Integrated eDiagnosis Approach (IeDA), centred on an electronic Clinical Decision Support System (eCDSS) developed in line with national Integrated Management of Childhood Illness (IMCI) guidelines, was implemented in primary health facilities of two regions of Burkina Faso. An evaluation was performed using a stepped-wedge cluster randomised design with the aim of determining whether the IeDA intervention increased Health Care Workers’ (HCW) adherence to the IMCI guidelines. Methods Ten randomly selected facilities per district were visited at each step by two trained nurses: One observed under-five consultations and the second conducted a repeat consultation. The primary outcomes were: overall adherence to clinical assessment tasks; overall correct classification ignoring the severity of the classifications; and overall correct prescription according to HCWs’ classifications. Statistical comparisons between trial arms were performed on cluster/step-level summaries. ...
Access to safe, effective, and affordable essential medicines (EM) is critical to quality health ... more Access to safe, effective, and affordable essential medicines (EM) is critical to quality health services and as such has played a key role in innovative health system strengthening approaches such as Performance-based Financing (PBF). Available literature indicates that PBF can improve EM availability, but has not done so consistently in the past. Qualitative explorations of the reasons are yet scarce. We contribute to expanding the literature by estimating the impact of PBF on EM availability and stockout in Burkina Faso and investigating mechanisms of and barriers to change. The study used an explanatory mixed methods design. The quantitative study component followed a quasi-experimental design (difference-in-differences), comparing how EM availability and stockout had changed three years after implementation in 12 PBF and in 12 control districts. Qualitative data was collected from purposely selected policy and implementation stakeholders at all levels of the health system and c...
Introduction: Stroke is a major public health concern. It is a frequent pathology, 80% of which i... more Introduction: Stroke is a major public health concern. It is a frequent pathology, 80% of which is of ischemic origin. Approximately 86% of all stroke deaths worldwide occur in low- and middle-income countries. The objective of this study was to investigate prognostic factors for in hospital lethality of stroke cases admitted in a public university hospital in Burkina Faso. Methods: This was a retrospective cohort study with a descriptive and analytical aim on adults admitted for a stroke confirmed by a brain scan at the Sourô Sanou University Teaching Hospital (CHUSS) of Bobo-Dioulasso over the period from January 1, 2009, to December 31, 2013. Results: The proportion of cases confirmed by the brain CT scan was 32% of all patients admitted for stroke in the CHUSS. The overall case fatality was 27.6%. This lethality was more pronounced in patients with hemorrhagic stroke (35.8%) compared to patients with ischemic stroke (22.4%). Median survival was higher in patients with ischemic s...
Additional file 5. Comparison of HCWs' performance with and without use of IMCI paper-forms i... more Additional file 5. Comparison of HCWs' performance with and without use of IMCI paper-forms in the control arm. (DOCX 18 kb)
Additional file 6. Agreement between HCWs and validation nurses' children measurements. 6b: A... more Additional file 6. Agreement between HCWs and validation nurses' children measurements. 6b: Agreement between HCWs and validation nurses' RDT results and caretakers' answers.
Additional file 4. Actual roll-out of the IeDA intervention with step dates and number (N) of chi... more Additional file 4. Actual roll-out of the IeDA intervention with step dates and number (N) of children aged 2–59 months observed at each step in each district.
The emergence of COVID-19 highlights globalisation realties, where diseases may emerge from anywh... more The emergence of COVID-19 highlights globalisation realties, where diseases may emerge from anywhere and rapidly spread globally. Lessons emphasise the necessity for strengthening regional and global collaboration and coordination to allow rapid risk identification, resource mobilisation and joint actions. We report the experience of the Regional Action through Data (RAD) partnership in fostering regional cooperation and collaboration to use data for battling infectious diseases and the effects of COVID-19. The Partnership comprised;BoadReach company, The West African Health Organization (WAHO) and the Intergovernmental Authority on Development (IGAD); Duke University Global Health Centre and the Jembi Health Systems, South Africa. Main objective: To address the problem of limited used of data to drive performance in healthcare service delivery in sub-Saharan Africa; by changing how and why data is collected, analysed, and then used to achieve results. Specific objectives: 1. Region...
Body fatness and physical activity (PA) among children should be measured accurately to address t... more Body fatness and physical activity (PA) among children should be measured accurately to address the pandemics of obesity and physical inactivity. Limited accurate PA data exist in the African region, and crude proxy measures of body composition (such as body mass index: BMI) and physical activity (such as questionnaires) may have limited most surveys and studies from the region. A stable isotope technique (deuterium dilution) and accelerometry provide ‘gold standards’ for validating measures of body fatness and PA, respectively. The consortium on “Reducing Obesity Using Nuclear Techniques to Design Interventions in Africa (ROUND-IT)” Study, therefore aimed to validate the accuracy of, 1) World Health Organisation’s (WHO) BMI-for-age as a means of assessing excessive body fatness; 2) the Physical Activity Questionnaire for Children (PAQ-C) as a means of measuring PA, and 3) to describe accelerometer-measured PA in a large African multi-country sample of children 6 – 11 years of age (...
Use of parametric statistical models can be a solution to reduce the follow-up period time requir... more Use of parametric statistical models can be a solution to reduce the follow-up period time required to estimate long-term survival. Mould and Boag were the first to use the lognormal model. Competing risks methodology seems more suitable when a particular event type is of interest than classical survival analysis. The objective was to evaluate the ability of the Jeong and Fine model to predict long-term cumulative incidence. Survival data recorded by Institut Curie (Paris) from 4761 breast cancer patients treated and followed between 1981 and 2013 were used. Long-term cumulative incidence rates predicted by the model using short-term follow-up data were compared to non-parametric estimation using complete follow-up data. 20-or 25-year cumulative incidence rates for loco-regional recurrence and distant metastasis predicted by the model using a maximum of 10 years of follow-up data had a maximum difference of around 6 % compared to nonparametric estimation. Prediction rates were underestimated for the third and composite event (contralateral or second cancer or death). Predictive ability of Jeong and Fine model on breast cancer data was generally good considering the short follow-up period time used for the estimation especially when a proportion of patient did not experience loco-regional recurrence or distant metastasis.
BackgroundThe exposure to parasites may influence the immune response to vaccines in endemic Afri... more BackgroundThe exposure to parasites may influence the immune response to vaccines in endemic African countries. In this study, we aimed to assess the association between helminth exposure to the most prevalent parasitic infections, schistosomiasis, soil transmitted helminths infection and filariasis, and the Ebola virus glycoprotein (EBOV GP) antibody concentration in response to vaccination with the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen in African and European participants using samples obtained from three international clinical trials.Methods/Principal FindingsWe conducted a study in a subset of participants in the EBL2001, EBL2002 and EBL3001 clinical trials that evaluated the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen against EVD in children, adolescents and adults from the United Kingdom, France, Burkina Faso, Cote d’Ivoire, Kenya, Uganda and Sierra Leone. Immune markers of helminth exposure at baseline were evaluated by ELISA with three commercial kits which detect IgG antibodi...
Background: In April 2016, Burkina Faso began free healthcare for children aged from 0 to 5 years... more Background: In April 2016, Burkina Faso began free healthcare for children aged from 0 to 5 years. However, its implementation faces challenges, and the goal of this study is to estimate the fees paid for this child care and to determine the causes of these direct payments. Methods: Data gathering involved 807 children aged from 0 to 5 years who had contact with the public healthcare system. The estimation of the determinants of out-of-pocket health payments involved the application of a two-part regression model. Results: About 31% of the children made out-of-pocket payments for healthcare (an average of 3407.77 CFA francs per case of illness). Of these, 96% paid for medicines and 24% paid for consultations. The first model showed that out-of-pocket payments were positively associated with hospitalization, urban area of residence, and severity of illness, were made in the East-Central and North-Central regions, and were negatively associated with the 7 to 23 month age range. The se...
Objective: to analyse the pandemic after one year in terms of the evolution of morbidity and mort... more Objective: to analyse the pandemic after one year in terms of the evolution of morbidity and mortality and factors that may contribute to this evolutionDesign: This is a secondary analysis of data gathered to respond to the COVID-19 pandemic. The number of cases, incidence rate, cumulative incidence rate, number of deaths, case fatality rate and their trends were analysed during the first year of the pandemic. Testing and other public health measures were also described according to the information available.Settings: The 15 States members of the Economic Community of West African States (ECOWAS) were considered.Results: As of 31st March 2021, the ECOWAS region reported 429,760 COVID-19 cases and 5,620 deaths. In the first year, 1,110.75 persons were infected per million, while 1.31% of the confirmed patients died. The ECOWAS region represents 30% of the African population. One year after the start of COVID-19 in ECOWAS, this region reported 10% of the cases and 10% of the deaths in...
Background: While maternal mortality has declined globally, it remains highest in low-income coun... more Background: While maternal mortality has declined globally, it remains highest in low-income countries. High-quality antenatal care (ANC) can control or decrease pregnancy-related complications for mothers and newborns. The implementation of performance-based financing (PBF) schemes in Sub-Saharan Africa to improve primary healthcare provision commonly includes mechanisms targeting ANC service quality. In this study, we examine changes in ANC provision produced by the introduction of a PBF scheme in rural Burkina Faso.Methods: This study followed a quasi-experimental design with two data collection points comparing effects on ANC service quality between primary health facilities across intervention and control districts based on difference-in-differences estimates. Outcome variables were defined using data on structural and process quality of care reflecting key clinical aspects of ANC provision (i.e. screening, prevention) for two different client groups (i.e. first ANC visits, fol...
The American Journal of Tropical Medicine and Hygiene
To reduce child mortality in children younger than 5 years, Burkina Faso has been offering free c... more To reduce child mortality in children younger than 5 years, Burkina Faso has been offering free care to this population of children since 2016. The free care program is aligned with the Integrated Management of Childhood Illness (IMCI) guidelines. Given that the number of studies that evaluated the competence of health-care workers (HCWs) during the free care program was limited, we assessed the adherence level of HCWs to the IMCI guidelines in the context of free care. This was a secondary data analysis. Data were obtained from a cross-sectional study conducted from July to September 2020 in 40 primary health-care centers and two district hospitals in the Hauts-Bassins region in Burkina Faso. Our analysis included 419 children younger than 5 years old who were consulted according to IMCI guidelines. Data were collected through direct observation using a checklist. The overall score of adherence of HCWs to IMCI guidelines was 57.8% (95% CI, 42.6–73.0). The mean adherence score of th...
Background The Integrated eDiagnosis Approach (IeDA), centred on an electronic Clinical Decision ... more Background The Integrated eDiagnosis Approach (IeDA), centred on an electronic Clinical Decision Support System (eCDSS) developed in line with national Integrated Management of Childhood Illness (IMCI) guidelines, was implemented in primary health facilities of two regions of Burkina Faso. An evaluation was performed using a stepped-wedge cluster randomised design with the aim of determining whether the IeDA intervention increased Health Care Workers’ (HCW) adherence to the IMCI guidelines. Methods Ten randomly selected facilities per district were visited at each step by two trained nurses: One observed under-five consultations and the second conducted a repeat consultation. The primary outcomes were: overall adherence to clinical assessment tasks; overall correct classification ignoring the severity of the classifications; and overall correct prescription according to HCWs’ classifications. Statistical comparisons between trial arms were performed on cluster/step-level summaries. ...
Access to safe, effective, and affordable essential medicines (EM) is critical to quality health ... more Access to safe, effective, and affordable essential medicines (EM) is critical to quality health services and as such has played a key role in innovative health system strengthening approaches such as Performance-based Financing (PBF). Available literature indicates that PBF can improve EM availability, but has not done so consistently in the past. Qualitative explorations of the reasons are yet scarce. We contribute to expanding the literature by estimating the impact of PBF on EM availability and stockout in Burkina Faso and investigating mechanisms of and barriers to change. The study used an explanatory mixed methods design. The quantitative study component followed a quasi-experimental design (difference-in-differences), comparing how EM availability and stockout had changed three years after implementation in 12 PBF and in 12 control districts. Qualitative data was collected from purposely selected policy and implementation stakeholders at all levels of the health system and c...
Introduction: Stroke is a major public health concern. It is a frequent pathology, 80% of which i... more Introduction: Stroke is a major public health concern. It is a frequent pathology, 80% of which is of ischemic origin. Approximately 86% of all stroke deaths worldwide occur in low- and middle-income countries. The objective of this study was to investigate prognostic factors for in hospital lethality of stroke cases admitted in a public university hospital in Burkina Faso. Methods: This was a retrospective cohort study with a descriptive and analytical aim on adults admitted for a stroke confirmed by a brain scan at the Sourô Sanou University Teaching Hospital (CHUSS) of Bobo-Dioulasso over the period from January 1, 2009, to December 31, 2013. Results: The proportion of cases confirmed by the brain CT scan was 32% of all patients admitted for stroke in the CHUSS. The overall case fatality was 27.6%. This lethality was more pronounced in patients with hemorrhagic stroke (35.8%) compared to patients with ischemic stroke (22.4%). Median survival was higher in patients with ischemic s...
Additional file 5. Comparison of HCWs' performance with and without use of IMCI paper-forms i... more Additional file 5. Comparison of HCWs' performance with and without use of IMCI paper-forms in the control arm. (DOCX 18 kb)
Additional file 6. Agreement between HCWs and validation nurses' children measurements. 6b: A... more Additional file 6. Agreement between HCWs and validation nurses' children measurements. 6b: Agreement between HCWs and validation nurses' RDT results and caretakers' answers.
Additional file 4. Actual roll-out of the IeDA intervention with step dates and number (N) of chi... more Additional file 4. Actual roll-out of the IeDA intervention with step dates and number (N) of children aged 2–59 months observed at each step in each district.
The emergence of COVID-19 highlights globalisation realties, where diseases may emerge from anywh... more The emergence of COVID-19 highlights globalisation realties, where diseases may emerge from anywhere and rapidly spread globally. Lessons emphasise the necessity for strengthening regional and global collaboration and coordination to allow rapid risk identification, resource mobilisation and joint actions. We report the experience of the Regional Action through Data (RAD) partnership in fostering regional cooperation and collaboration to use data for battling infectious diseases and the effects of COVID-19. The Partnership comprised;BoadReach company, The West African Health Organization (WAHO) and the Intergovernmental Authority on Development (IGAD); Duke University Global Health Centre and the Jembi Health Systems, South Africa. Main objective: To address the problem of limited used of data to drive performance in healthcare service delivery in sub-Saharan Africa; by changing how and why data is collected, analysed, and then used to achieve results. Specific objectives: 1. Region...
Body fatness and physical activity (PA) among children should be measured accurately to address t... more Body fatness and physical activity (PA) among children should be measured accurately to address the pandemics of obesity and physical inactivity. Limited accurate PA data exist in the African region, and crude proxy measures of body composition (such as body mass index: BMI) and physical activity (such as questionnaires) may have limited most surveys and studies from the region. A stable isotope technique (deuterium dilution) and accelerometry provide ‘gold standards’ for validating measures of body fatness and PA, respectively. The consortium on “Reducing Obesity Using Nuclear Techniques to Design Interventions in Africa (ROUND-IT)” Study, therefore aimed to validate the accuracy of, 1) World Health Organisation’s (WHO) BMI-for-age as a means of assessing excessive body fatness; 2) the Physical Activity Questionnaire for Children (PAQ-C) as a means of measuring PA, and 3) to describe accelerometer-measured PA in a large African multi-country sample of children 6 – 11 years of age (...
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