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Peter Byass,
Daniel Chandramohan,
Samuel J Clark,
Lucia D'Ambruoso, Edward Fottrell,
Wendy J Graham,
Abraham J Herbst,
Abraham Hodgson,
Sennen Hounton,
Kathleen Kahn,
Anand Krishnan,
Jordana Leitao,
Frank Odhiambo,
Osman A Sankoh,
Stephen M Tollman
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ABSTRACT: Verbal autopsy (VA) is the only available approach for determining the cause of many deaths, where routine certification is not in place. Therefore, it is important to use standards and methods for VA that maximise efficiency, consistency and comparability. The World Health Organization (WHO) has led the development of the 2012 WHO VA instrument as a new standard, intended both as a research tool and for routine registration of deaths.
A new public-domain probabilistic model for interpreting VA data, InterVA-4, is described, which builds on previous versions and is aligned with the 2012 WHO VA instrument.
The new model has been designed to use the VA input indicators defined in the 2012 WHO VA instrument and to deliver causes of death compatible with the International Classification of Diseases version 10 (ICD-10) categorised into 62 groups as defined in the 2012 WHO VA instrument. In addition, known shortcomings of previous InterVA models have been addressed in this revision, as well as integrating other work on maternal and perinatal deaths.
The InterVA-4 model is presented here to facilitate its widespread use and to enable further field evaluation to take place. Results from a demonstration dataset from Agincourt, South Africa, show continuity of interpretation between InterVA-3 and InterVA-4, as well as differences reflecting specific issues addressed in the design and development of InterVA-4.
InterVA-4 is made freely available as a new standard model for interpreting VA data into causes of death. It can be used for determining cause of death both in research settings and for routine registration. Further validation opportunities will be explored. These developments in cause of death registration are likely to substantially increase the global coverage of cause-specific mortality data.
Global Health Action 01/2012; 5:1-8. · 1.27 Impact Factor
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ABSTRACT: Cases of premature death in Africa may be attributed to witchcraft. In such settings, medical registration of causes of death is rare. To fill this gap, verbal autopsy (VA) methods record signs and symptoms of the deceased before death as well as lay opinion regarding the cause of death; this information is then interpreted to derive a medical cause of death. In the Agincourt Health and Demographic Surveillance Site, South Africa, around 6% of deaths are believed to be due to 'bewitchment' by VA respondents.
Using 6874 deaths from the Agincourt Health and Socio-Demographic Surveillance System, the epidemiology of deaths reported as bewitchment was explored, and using medical causes of death derived from VA, the association between perceptions of witchcraft and biomedical causes of death was investigated.
The odds of having one's death reported as being due to bewitchment is significantly higher in children and reproductive-aged women (but not in men) than in older adults. Similarly, sudden deaths or those following an acute illness, deaths occurring before 2001 and those where traditional healthcare was sought are more likely to be reported as being due to bewitchment. Compared with all other deaths, deaths due to external causes are significantly less likely to be attributed to bewitchment, while maternal deaths are significantly more likely to be.
Understanding how societies interpret the essential factors that affect their health and how health seeking is influenced by local notions and perceived aetiologies of illness and death could better inform sustainable interventions and health promotion efforts.
Journal of epidemiology and community health 04/2011; 66(8):704-9. · 3.04 Impact Factor
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Edward Fottrell
Population Health Metrics 01/2011; 9:24. · 2.11 Impact Factor
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ABSTRACT: Verbal autopsy (VA) is a widely used method for analyzing cause of death in absence of vital registration systems. We adapted the InterVA method to extrapolate causes of death for stillbirths and neonatal deaths from verbal autopsy questionnaires, using data from Malawi, Zimbabwe, and Nepal.
We obtained 734 stillbirth and neonatal VAs from recent community studies in rural areas: 169 from Malawi, 385 from Nepal, and 180 from Zimbabwe. Initial refinement of the InterVA model was based on 100 physician-reviewed VAs from Malawi. InterVA indicators and matrix probabilities for cause of death were reviewed for clinical and epidemiological coherence by a pediatrician-researcher and an epidemiologist involved in the development of InterVA. The modified InterVA model was evaluated by comparing population-level cause-specific mortality fractions and individual agreement from two methods of interpretation (physician review and InterVA) for a further 69 VAs from Malawi, 385 from Nepal, and 180 from Zimbabwe.
Case-by-case agreement between InterVA and reviewing physician diagnoses for 69 cases from Malawi, 180 cases from Zimbabwe, and 385 cases from Nepal were 83% (kappa 0.76 (0.75 - 0.80)), 71% (kappa 0.41(0.32-0.51)), and 74% (kappa 0.63 (0.60-0.63)), respectively. The proportion of stillbirths identified as fresh or macerated by the different methods of VA interpretation was similar in all three settings. Comparing across countries, the modified InterVA method found that proportions of preterm births and deaths due to infection were higher in Zimbabwe (44%) than in Malawi (28%) or Nepal (20%).
The modified InterVA method provides plausible results for stillbirths and newborn deaths, broadly comparable to physician review but with the advantage of internal consistency. The method allows standardized cross-country comparisons and eliminates the inconsistencies of physician review in such comparisons.
Population Health Metrics 01/2011; 9:48. · 2.11 Impact Factor
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ABSTRACT: Verbal autopsy (VA) has often been used for point estimates of cause-specific mortality, but seldom to characterize long-term changes in epidemic patterns. Monitoring emerging causes of death involves practitioners' developing perceptions of diseases and demands consistent methods and practices. Here we retrospectively analyze HIV-related mortality in South Africa, using physician and modeled interpretation.
Between 1992 and 2005, 94% of 6,153 deaths which occurred in the Agincourt subdistrict had VAs completed, and coded by two physicians and the InterVA model. The physician causes of death were consolidated into a single consensus underlying cause per case, with an additional physician arbitrating where different diagnoses persisted. HIV-related mortality rates and proportions of deaths coded as HIV-related by individual physicians, physician consensus, and the InterVA model were compared over time.
Approximately 20% of deaths were HIV-related, ranging from early low levels to tenfold-higher later population rates (2.5 per 1,000 person-years). Rates were higher among children under 5 years and adults 20 to 64 years. Adult mortality shifted to older ages as the epidemic progressed, with a noticeable number of HIV-related deaths in the over-65 year age group latterly. Early InterVA results suggested slightly higher initial HIV-related mortality than physician consensus found. Overall, physician consensus and InterVA results characterized the epidemic very similarly. Individual physicians showed marked interobserver variation, with consensus findings generally reflecting slightly lower proportions of HIV-related deaths. Aggregated findings for first versus second physician did not differ appreciably.
VA effectively detected a very significant epidemic of HIV-related mortality. Using either physicians or InterVA gave closely comparable findings regarding the epidemic. The consistency between two physician coders per case (from a pool of 14) suggests that double coding may be unnecessary, although the consensus rate of HIV-related mortality was approximately 8% lower than by individual physicians. Consistency within and between individual physicians, individual perceptions of epidemic dynamics, and the inherent consistency of models are important considerations here. The ability of the InterVA model to track a more than tenfold increase in HIV-related mortality over time suggests that finely tuned "local" versions of models for VA interpretation are not necessary.
Population Health Metrics 01/2011; 9:46. · 2.11 Impact Factor
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ABSTRACT: InterVA is a probabilistic method for interpreting verbal autopsy (VA) data. It uses a priori approximations of probabilities relating to diseases and symptoms to calculate the probability of specific causes of death given reported symptoms recorded in a VA interview. The extent to which InterVA's ability to characterise a population's mortality composition might be sensitive to variations in these a priori probabilities was investigated.
A priori InterVA probabilities were changed by 1, 2 or 3 steps on the logarithmic scale on which the original probabilities were based. These changes were made to a random selection of 25% and 50% of the original probabilities, giving six model variants. A random sample of 1,000 VAs from South Africa, were used as a basis for experimentation and were processed using the original InterVA model and 20 random instances of each of the six InterVA model variants. Rank order of cause of death and cause-specific mortality fractions (CSMFs) from the original InterVA model and the mean, maximum and minimum results from the 20 randomly modified InterVA models for each of the six variants were compared.
CSMFs were functionally similar between the original InterVA model and the models with modified a priori probabilities such that even the CSMFs based on the InterVA model with the greatest degree of variation in the a priori probabilities would not lead to substantially different public health conclusions. The rank order of causes were also similar between all versions of InterVA.
InterVA is a robust model for interpreting VA data and even relatively large variations in a priori probabilities do not affect InterVA-derived results to a great degree. The original physician-derived a priori probabilities are likely to be sufficient for the global application of InterVA in settings without routine death certification.
PLoS ONE 01/2011; 6(11):e27200. · 4.09 Impact Factor
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ABSTRACT: To demonstrate the viability and value of comparing cause-specific mortality across four socioeconomically and culturally diverse settings using a completely standardised approach to VA interpretation.
Deaths occurring between 1999 and 2004 in Butajira (Ethiopia), Agincourt (South Africa), FilaBavi (Vietnam) and Purworejo (Indonesia) health and socio-demographic surveillance sites were identified. VA interviews were successfully conducted with the caregivers of the deceased to elicit information on signs and symptoms preceding death. The information gathered was interpreted using the InterVA method to derive population cause-specific mortality fractions for each of the four settings.
The mortality profiles derived from 4784 deaths using InterVA illustrate the potential of the method to characterise sub-national profiles well. The derived mortality patterns illustrate four populations with plausible, markedly different disease profiles, apparently at different stages of health transition.
Given the standardised method of VA interpretation, the observed differences in mortality cannot be because of local differences in assigning cause of death. Standardised, fit-for-purpose methods are needed to measure population health and changes in mortality patterns so that appropriate health policy and programmes can be designed, implemented and evaluated over time and place. The InterVA approach overcomes several longstanding limitations of existing methods and represents a valuable tool for health planners and researchers in resource-poor settings.
Tropical Medicine & International Health 10/2010; 15(10):1256-65. · 2.80 Impact Factor
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ABSTRACT: To document the impact of severe obstetric complications on post-partum health in mothers and mortality in babies over 12 months in Benin and to assess whether severe complications associated with perinatal death are particularly likely to lead to adverse health consequences.
Cohort study which followed women and their babies after a severe complication or an uncomplicated childbirth. Women were selected in hospitals and interviewed at home at discharge, and at 6 and 12 months post-partum. Women were invited for a medical check-up at 6 months and 12 months.
The cohort includes 205 women with severe complications and a live birth, 64 women with severe complications and perinatal death and 440 women with uncomplicated delivery. Women with severe complications and a live birth were not dissimilar to women with a normal delivery in terms of post-partum health, except for hypertension [adjusted OR = 5.8 (1.9-17.0)], fever [adjusted OR = 1.71 (1.1-2.8)] and infant mortality [adjusted OR = 11.0 (0.8-158.2)]. Women with complications and perinatal death were at increased risk of depression [adjusted OR = 3.4 (1.3-9.0)], urine leakages [adjusted OR = 2.7 (1.2-5.8)], and to report poor health [adjusted OR = 5.27 (2.2-12.4)] and pregnancy's negative effects on their life [adjusted OR = 4.11 (1.9-9.0)]. Uptake of post-natal services was poor in all groups.
Women in developing countries face a high risk of severe complications during pregnancy and delivery. These can lead to adverse consequences for their own health and that of their offspring. Resources are needed to ensure that pregnant women receive adequate care before, during and after discharge from hospital. Near-miss women with a perinatal death appear a particularly high-risk group.
Tropical Medicine & International Health 06/2010; 15(6):733-42. · 2.80 Impact Factor
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ABSTRACT: Objective To document the impact of severe obstetric complications on post-partum health in mothers and mortality in babies over 12 months in Benin and to assess whether severe complications associated with perinatal death are particularly likely to lead to adverse health consequences.Methods Cohort study which followed women and their babies after a severe complication or an uncomplicated childbirth. Women were selected in hospitals and interviewed at home at discharge, and at 6 and 12 months post-partum. Women were invited for a medical check-up at 6 months and 12 months.Results The cohort includes 205 women with severe complications and a live birth, 64 women with severe complications and perinatal death and 440 women with uncomplicated delivery. Women with severe complications and a live birth were not dissimilar to women with a normal delivery in terms of post-partum health, except for hypertension [adjusted OR = 5.8 (1.9–17.0)], fever [adjusted OR = 1.71 (1.1–2.8)] and infant mortality [adjusted OR = 11.0 (0.8–158.2)]. Women with complications and perinatal death were at increased risk of depression [adjusted OR = 3.4 (1.3–9.0)], urine leakages [adjusted OR = 2.7 (1.2–5.8)], and to report poor health [adjusted OR = 5.27 (2.2–12.4)] and pregnancy’s negative effects on their life [adjusted OR = 4.11 (1.9–9.0)]. Uptake of post-natal services was poor in all groups.Conclusion Women in developing countries face a high risk of severe complications during pregnancy and delivery. These can lead to adverse consequences for their own health and that of their offspring. Resources are needed to ensure that pregnant women receive adequate care before, during and after discharge from hospital. Near-miss women with a perinatal death appear a particularly high-risk group.Effets des complications obstétriques graves sur la santé des femmes et la mortalité infantile au BéninObjectif: Documenter l’impact des complications obstétriques graves sur la santé post-partum des mères et la mortalité chez les bébés sur 12 mois au Bénin et évaluer si des complications graves associées à la mortalité périnatale sont particulièrement susceptibles d’entraîner des conséquences néfastes sur la santé.Méthodes: Etude de cohorte où les femmes et leurs bébés ont été suivis après un accouchement avec une complication grave ou sans complications. Les femmes ont été sélectionnées dans les hôpitaux et interviewées à domicile après la sorite de l’hôpital et à 6 et 12 mois après l’accouchement. Elles ont été invitées pour un bilan médical à 6 mois et 12 mois.Résultats: La cohorte comprenait 205 femmes avec des complications graves et une naissance vivante, 64 femmes avec des complications graves et un décès périnatal et 440 femmes avec un accouchement sans complication. Il n’y avait pas de différentes entre les femmes avec des complications graves et une naissance vivante et les femmes avec un accouchement normal en termes de santé postpartum, à l’exception de l’hypertension artérielle (OR ajusté = 5,8; [1,9-17,0]), la fièvre (OR ajusté = 1,71; [1.1-2.8]) et la mortalité infantile (OR ajusté = 11,0; [0,8-158,2]). Les femmes avec des complications et un décès périnatal du bébé avaient un risque accru de dépression (OR ajusté = 3,4; [1,3-9,0], de pertes d’urine (OR ajusté = 2,7; [1,2-5,8]) et de rapporter une mauvaise santé (OR ajusté = 5,27; [2,2-12,4] et des effets négatifs de la grossesse sur leur vie (OR ajusté = 4,11; [1,9-9,0]). Le recours aux services postnataux était faible dans tous les groupes.Conclusion: Les femmes dans les pays en développement sont confrontées à un risque élevé de complications graves pendant la grossesse et l’accouchement. Celles-ci peuvent mener à des conséquences négatives pour leur propre santé et celle de leur progéniture. Des ressources sont nécessaires afin d’assurer aux femmes enceintes des soins appropriés avant, pendant et après la sortie de l’hôpital. Les femmes avec un décès périnatal du bébé et qui ont frôlé la mort constituent particulièrement un groupe à risque élevé.Efectos de las complicaciones obstétricas severas en la salud femenina y la mortalidad infantil en BeninObjetivo: Documentar el impacto de las complicaciones obstétricas severas sobre la salud postparto en madres y la mortalidad en bebés durante 12 meses en Benin; y evaluar si las complicaciones severas asociadas a la muerte perinatal son particularmente propensas a resultar en consecuencias severas para la salud materna.Métodos: Estudio de cohortes que siguió a mujeres y a sus bebés después de complicaciones severas o de un parto sin complicaciones. Las mujeres fueron seleccionadas en hospitales y entrevistadas en sus hogares después de haber recibido el alta, y trás 6 y 12 meses de haber dado a luz.Resultados: La cohorte incluye a 205 mujeres con complicaciones severas y un parto de nacido vivo, 64 mujeres con complicaciones severas y muerte perinatal y 440 mujeres con un parto sin complicaciones. Las mujeres con complicaciones severas y un parto de nacido vivo no eran muy diferentes a las mujeres con un parto normal en términos de salud post parto, excepto por la hipertensión (OR ajustado =5.8 (1.9-17.0)), fiebre (OR ajustado=1.71, (1.1-2.8)) y mortalidad infantil (OR ajustado=11.0 (0.8-158.2). Las mujeres con complicaciones y muerte perinatal tenían mayor riesgo de depresión (OR ajustado=3.4 (1.3-9.0), pérdida de orina (OR ajustado=2.7 (1.2-5.8), y de reportar mala salud (OR ajustado=5.27 (2-2-12.4) y efectos negativos del embarazo en su vida (OR ajustado=4.11 (1.9-9.0). El uso de los servicios postparto era escaso en ambos grupos.Conclusiones: Las mujeres en países en vías de desarrollo se enfrentan a un alto riesgo de complicaciones severas durante el embarazo y el parto. Estos pueden conllevar a consecuencias adversas para su propia salud y la de su hijo. Se necesitan recursos para asegurar que las mujeres embarazadas reciben un cuidado adecuado antes, durante y después de ser dadas de alta del hospital. Las mujeres con complicaciones en el parto y muerte perinatal son en particular un grupo de alto riesgo.
Tropical Medicine & International Health 04/2010; 15(6):733 - 742. · 2.80 Impact Factor
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ABSTRACT: Understanding of global health and changing morbidity and mortality is limited by inadequate measurement of population health. With fewer than one-third of deaths worldwide being assigned a cause, this long-standing dearth of information, almost exclusively in the world's poorest countries, hinders understanding of population health and limits opportunities for planning, monitoring, and evaluating interventions. In the absence of routine death registration, verbal autopsy (VA) methods are used to derive probable causes of death. Much effort has been put into refining the approach for specific purposes; however, there has been a lack of harmony regarding such efforts. Subsequently, a variety of methods and principles have been developed, often focusing on a single aspect of VA, and the resulting literature provides an inconsistent picture. By reviewing methodological and conceptual issues in VA, it is evident that VA cannot be reduced to a single one-size-fits-all tool. VA must be contextualized; given the lack of "gold standards," methodological developments should not be considered in terms of absolute validity but rather in terms of consistency, comparability, and adequacy for the intended purpose. There is an urgent need for clarified thinking about the overall objectives of population-level cause-of-death measurement and harmonized efforts in empirical methodological research.
Epidemiologic Reviews 03/2010; 32(1):38-55. · 7.58 Impact Factor
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ABSTRACT: Little is known about the impact of life-threatening obstetric complications ('near miss') on women's mental health in low- and middle-income countries.
To examine the relationships between near miss and postpartum psychological distress in the Republic of Benin.
One-year prospective cohort using epidemiological and ethnographic techniques in a population of women delivering at health facilities.
In total 694 women contributed to the study. Except when associated with perinatal death, near-miss events were not associated with greater risk of psychological distress in the 12 months postpartum compared with uncomplicated childbirth. Much of the direct effect of near miss with perinatal death on increased risk of psychological distress was shown to be mediated through wider consequences of traumatic childbirth.
A live baby protects near-miss women from increased vulnerability by giving a positive element in their lives that helps them cope and reduces their risk of psychological distress. Near-miss women with perinatal death should be targeted early postpartum to prevent or treat the development of depressive symptoms.
The British journal of psychiatry: the journal of mental science 01/2010; 196(1):18-25. · 6.62 Impact Factor
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ABSTRACT: Cause of death data are an essential source for public health planning, but their availability and quality are lacking in many parts of the world. Interviewing family and friends after a death has occurred (a procedure known as verbal autopsy) provides a source of data where deaths otherwise go unregistered; but sound methods for interpreting and analysing the ensuing data are essential. Two main approaches are commonly used: either physicians review individual interview material to arrive at probable cause of death, or probabilistic models process the data into likely cause(s). Here we compare and contrast these approaches as applied to a series of 6,153 deaths which occurred in a rural South African population from 1992 to 2005. We do not attempt to validate either approach in absolute terms.
The InterVA probabilistic model was applied to a series of 6,153 deaths which had previously been reviewed by physicians. Physicians used a total of 250 cause-of-death codes, many of which occurred very rarely, while the model used 33. Cause-specific mortality fractions, overall and for population subgroups, were derived from the model's output, and the physician causes coded into comparable categories. The ten highest-ranking causes accounted for 83% and 88% of all deaths by physician interpretation and probabilistic modelling respectively, and eight of the highest ten causes were common to both approaches. Top-ranking causes of death were classified by population subgroup and period, as done previously for the physician-interpreted material. Uncertainty around the cause(s) of individual deaths was recognised as an important concept that should be reflected in overall analyses. One notably discrepant group involved pulmonary tuberculosis as a cause of death in adults aged over 65, and these cases are discussed in more detail, but the group only accounted for 3.5% of overall deaths.
There were no differences between physician interpretation and probabilistic modelling that might have led to substantially different public health policy conclusions at the population level. Physician interpretation was more nuanced than the model, for example in identifying cancers at particular sites, but did not capture the uncertainty associated with individual cases. Probabilistic modelling was substantially cheaper and faster, and completely internally consistent. Both approaches characterised the rise of HIV-related mortality in this population during the period observed, and reached similar findings on other major causes of mortality. For many purposes probabilistic modelling appears to be the best available means of moving from data on deaths to public health actions. Please see later in the article for the Editors' Summary.
PLoS Medicine 01/2010; 7(8):e1000325. · 16.27 Impact Factor
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Hailemariam Lemma,
Peter Byass,
Alem Desta,
Andrea Bosman,
Gianfranco Costanzo,
Luigi Toma, Edward Fottrell,
Anne-Claire Marrast,
Yohannes Ambachew,
Asefaw Getachew,
Nathan Mulure,
Aldo Morrone,
Angela Bianchi,
Gebre Ab Barnabas
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ABSTRACT: Objective To assess the impact and feasibility of artemether-lumefantrine deployment at community level, combined with phased introduction of rapid diagnostic tests (RDTs), on malaria transmission, morbidity, and mortality and health service use in a remote area of Ethiopia.Methods Two-year pilot study in two districts: artemether-lumefantrine was prescribed after parasitological confirmation of malaria in health facilities in both districts. In the intervention district, artemether-lumefantrine was also made available through 33 community health workers (CHWs); of these, 50% were equipped with RDTs in the second year.Results At health facilities; 54 774 patients in the intervention and 100 535 patients in the control district were treated for malaria. In the intervention district, 75 654 patients were treated for malaria by community health workers. Use of RDTs in Year 2 excluded non-Plasmodium falciparumin 89.7% of suspected cases. During the peak of malaria transmission in 2005, the crude parasite prevalence was 7.4% (95% CI: 6.1–8.9%) in the intervention district and 20.8% (95% CI: 18.7–23.0%) in the control district. Multivariate modelling indicated no significant difference in risk of all-cause mortality between the intervention and the control districts [adjusted incidence rate ratio (aIRR) 1.03, 95%CI 0.87–1.21, P = 0.751], but risk of malaria-specific mortality was lower in the intervention district (aIRR 0.60, 95%CI 0.40–0.90, P = 0.013).Conclusions Artemether-lumefantrine deployment through a community-based service in a remote rural population reduced malaria transmission, lowered the malaria case burden for health facilities and reduced malaria morbidity and mortality during a 2-year period which included a major malaria epidemic.Déploiement de l’artéméther-luméfantrine et du test rapide dans des communautés éthiopiennes: impact sur la morbidité, la mortalité et les ressources de la santé pour la malariaObjectif: Evaluer l’impact et la faisabilité du déploiement de l’artéméther-luméfantrine à l’échelle communautaire, combinée avec l’introduction progressive de tests rapides de diagnostic, sur la morbidité et la mortalité de la malaria et sur l’utilisation des services de santé dans une région reculée d’Éthiopie.Méthodes: Etude pilote de 2 ans an dans deux districts: l’artéméther-luméfantrine a été prescrit après confirmation parasitologique de la malaria dans les services de santé dans les deux districts. Dans le district d’intervention, l’artéméther-luméfantrine a été rendu disponible chez 33 agents de santé communautaires; 50% de ceux-ci étaient équipés de tests rapides de diagnostic durant la deuxième année.Résultats: 54.774 patients atteints de malaria ont été soignés dans les services de santé dans le district d’intervention et 100.535 dans le district témoins. 75.654 patients atteints de malaria ont été traités par des agents de santé communautaires dans le district d’intervention. L’utilisation de tests rapides de diagnostic dans l’année 2 a permis d’exclure les non P. falciparum dans 89,7% des cas suspects. Durant le pic de transmission de la malaria en 2005, la prévalence parasitaire brute était de 7,4% (IC95%: 6,1-8,9%) dans le district d’intervention et de 20,8% (IC95%: 18,7-23,0%) dans le district témoins. L’analyse multivariée n’a indiqué aucune différence significative du risque de mortalité de toutes causes confondues entre les districts d’intervention et témoins (ratio ajusté des taux d’incidence [AIRr]: 1,03; IC95% : 0, 87-1,21 ; p = 0,751), mais le risque de mortalité spécifique à la malaria était plus faible dans le district d’intervention (AIRr : 0,60, IC95%: 0,40-0,90 ; p = 0, 013).Conclusions: Le déploiement de l’artéméther-luméfantrine à travers un service basé sur la communauté dans une population rurale a réduit la transmission de la malaria, a diminué la charge liées aux cas de malaria pour les services de santé et a réduit la morbidité et la mortalité de la malaria au cours d’une période de deux ans couvrant une épidémie majeure de malaria.Desplegando la artemeter-lumefantrina con pruebas rápidas en comunidades Etiopes: impacto sobre la morbilidad de malaria, mortalidad y recursos sanitarios.Objetivo: Evaluar el impacto y la viabilidad del despliegue a nivel comunitario de artemeter-lumefantrina, combinado con la introducción por fases de pruebas de diagnóstico rápido, sobre la morbilidad de malaria, mortalidad y uso de servicios sanitarios en un área remota de Etiopía.Métodos: Estudio piloto de 2-años en dos distritos: se prescribió artemeter-lumefantrina después de la confirmación parasitológica de malaria en centros sanitarios de ambos distritos. En el distrito de la intervención, el artemeter-lumefantrina también estaba disponible a través de 33 trabajadores sanitarios comunitarios; de estos, 50% estaban equipados con pruebas diagnósticas rápidas en el segundo año.Resultados: Se trataron 54,774 pacientes con malaria en los centros sanitarios del distrito intervenido y 100,535 en el distrito control. 75,654 pacientes con malaria fueron tratados por trabajadores sanitarios comunitarios en el distrito de intervención. El uso de pruebas diagnósticas rápidas en el Año 2 excluyó no-P. falciparum en 89·7% de los casos sospechosos. Durante el pico de transmisión de la malaria en el 2005, la prevalencia parasitaria cruda era 7.4% (95% IC: 6.1-8.9%) en el distrito de la intervención y 20.8% (95% IC: 18.7-23.0%) en el distrito control. Los modelos multivariados indicaban que no había diferencias significativas en el riesgo de mortalidad por cualquier causa entre los distritos de intervención y control (razón de tasas de la incidencia ajustado [aIRR] 1·03, 95%IC 0·87-1·21, p = 0·751), pero el riesgo de mortalidad específica por malaria era menor en el distrito de la intervención (aIRR 0·60, 95%CI 0·40-0·90, p = 0·013).Conclusiones: El despliegue de artemeter-lumefantrina mediante un servicio basado en la comunidad en una población rural remota, redujo la transmisión de malaria, disminuyó la carga por casos de malaria en los centros sanitarios, y redujo la morbilidad y mortalidad por malaria durante un periodo de dos años que incluyeron una gran epidemia de malaria.
Tropical Medicine & International Health 12/2009; 15(2):241 - 250. · 2.80 Impact Factor
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Hailemariam Lemma,
Peter Byass,
Alem Desta,
Andrea Bosman,
Gianfranco Costanzo,
Luigi Toma, Edward Fottrell,
Anne-Claire Marrast,
Yohannes Ambachew,
Asefaw Getachew,
Nathan Mulure,
Aldo Morrone,
Angela Bianchi,
Gebre Ab Barnabas
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[hide abstract]
ABSTRACT: To assess the impact and feasibility of artemether-lumefantrine deployment at community level, combined with phased introduction of rapid diagnostic tests (RDTs), on malaria transmission, morbidity, and mortality and health service use in a remote area of Ethiopia.
Two-year pilot study in two districts: artemether-lumefantrine was prescribed after parasitological confirmation of malaria in health facilities in both districts. In the intervention district, artemether-lumefantrine was also made available through 33 community health workers (CHWs); of these, 50% were equipped with RDTs in the second year.
At health facilities; 54 774 patients in the intervention and 100 535 patients in the control district were treated for malaria. In the intervention district, 75 654 patients were treated for malaria by community health workers. Use of RDTs in Year 2 excluded non-Plasmodium falciparumin 89.7% of suspected cases. During the peak of malaria transmission in 2005, the crude parasite prevalence was 7.4% (95% CI: 6.1-8.9%) in the intervention district and 20.8% (95% CI: 18.7-23.0%) in the control district. Multivariate modelling indicated no significant difference in risk of all-cause mortality between the intervention and the control districts [adjusted incidence rate ratio (aIRR) 1.03, 95%CI 0.87-1.21, P = 0.751], but risk of malaria-specific mortality was lower in the intervention district (aIRR 0.60, 95%CI 0.40-0.90, P = 0.013).
Artemether-lumefantrine deployment through a community-based service in a remote rural population reduced malaria transmission, lowered the malaria case burden for health facilities and reduced malaria morbidity and mortality during a 2-year period which included a major malaria epidemic.
Tropical Medicine & International Health 12/2009; 15(2):241-50. · 2.80 Impact Factor
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Edward Fottrell
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ABSTRACT: Reliable cause-specific mortality data constitute a crucial resource for health monitoring, service planning and prioritisation. However, in the majority of the world's poorest settings, systematic health and vital event surveillance systems are weak or non-existent. As such, deaths are not counted and causes of death remain unregistered for more than two-thirds of the world's population.For researchers, health workers and policy makers in resource-poor settings, therefore, attempts to measure mortality have to be implemented from first principles. As a result, there is wide variation in mortality surveillance methodologies in different settings, and lack of standardisation and rigorous validation of these methods hinder meaningful comparison of mortality data between settings and over time.With a particular focus on Health and Demographic Surveillance Systems (HDSSs), this paper summarises recent research and conceptual development of certain methodological aspects of mortality surveillance stemming from a series of empirical investigations. The paper describes the advantages and limitations of various methods in particular contexts, and argues that there is no single methodology to satisfy all data needs. Rather, methodological decisions about mortality measurement should be a synthesis of all available knowledge relating to clearly defined concepts of why data are being collected, how they can be used and when they are of good enough quality to inform public health action.
Global Health Action 01/2009; 2. · 1.27 Impact Factor
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ABSTRACT: To assess our experiences of using hand-held computers (personal digital assistants, PDAs) for direct data capture in a large community-based geo-referenced survey in rural Burkina Faso, highlighting benefits and lessons learnt from their use.
A population-based geo-referenced survey of over 500 000 people was undertaken using PDAs with in-built GPS receivers and the resulting database analysed in terms of successful completion, error rates and interview durations.
Surveys were successfully completed for 84 861 households (98.3%) by 127 interviewers. The data input error rate was assessed at 0.24%, with more than half of the errors being made by less than 10% of the interviewers. Faster interviewers were not less accurate. Time-stamped and geo-referenced data allowed reconstruction of particular interviewer-day activities.
Although the survey setting was challenging, the feasibility of using direct data capture on a large scale was well established. We learnt that, with more experience, we could have made better use of real-time entry and quality control checking procedures. The work involved in designing and setting up a complex survey on PDAs prior to data collection should not be underestimated.
Tropical Medicine & International Health 07/2008; 13 Suppl 1:25-30. · 2.80 Impact Factor
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ABSTRACT: As in any measurement process, a certain amount of error may be expected in routine population surveillance operations such as those in demographic surveillance sites (DSSs). Vital events are likely to be missed and errors made no matter what method of data capture is used or what quality control procedures are in place. The extent to which random errors in large, longitudinal datasets affect overall health and demographic profiles has important implications for the role of DSSs as platforms for public health research and clinical trials. Such knowledge is also of particular importance if the outputs of DSSs are to be extrapolated and aggregated with realistic margins of error and validity.
This study uses the first 10-year dataset from the Butajira Rural Health Project (BRHP) DSS, Ethiopia, covering approximately 336,000 person-years of data. Simple programmes were written to introduce random errors and omissions into new versions of the definitive 10-year Butajira dataset. Key parameters of sex, age, death, literacy and roof material (an indicator of poverty) were selected for the introduction of errors based on their obvious importance in demographic and health surveillance and their established significant associations with mortality. Defining the original 10-year dataset as the 'gold standard' for the purposes of this investigation, population, age and sex compositions and Poisson regression models of mortality rate ratios were compared between each of the intentionally erroneous datasets and the original 'gold standard' 10-year data.
The composition of the Butajira population was well represented despite introducing random errors, and differences between population pyramids based on the derived datasets were subtle. Regression analyses of well-established mortality risk factors were largely unaffected even by relatively high levels of random errors in the data.
The low sensitivity of parameter estimates and regression analyses to significant amounts of randomly introduced errors indicates a high level of robustness of the dataset. This apparent inertia of population parameter estimates to simulated errors is largely due to the size of the dataset. Tolerable margins of random error in DSS data may exceed 20%. While this is not an argument in favour of poor quality data, reducing the time and valuable resources spent on detecting and correcting random errors in routine DSS operations may be justifiable as the returns from such procedures diminish with increasing overall accuracy. The money and effort currently spent on endlessly correcting DSS datasets would perhaps be better spent on increasing the surveillance population size and geographic spread of DSSs and analysing and disseminating research findings.
BMC Medical Research Methodology 02/2008; 8:13. · 2.67 Impact Factor
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ABSTRACT: Population-based sample surveys and sentinel surveillance methods are commonly used as substitutes for more widespread health and demographic monitoring and intervention studies in resource-poor settings. Such methods have been criticised as only being worthwhile if the results can be extrapolated to the surrounding 100-fold population. With an emphasis on measuring mortality, this study explores the extent to which choice of sampling method affects the representativeness of 1% sample data in relation to various demographic and health parameters in a rural, developing-country setting.
Data from a large community based census and health survey conducted in rural Burkina Faso were used as a basis for modelling. Twenty 1% samples incorporating a range of health and demographic parameters were drawn at random from the overall dataset for each of seven different sampling procedures at two different levels of local administrative units. Each sample was compared with the overall 'gold standard' survey results, thus enabling comparisons between the different sampling procedures.
All sampling methods and parameters tested performed reasonably well in representing the overall population. Nevertheless, a degree of variation could be observed both between sampling approaches and between different parameters, relating to their overall distribution in the total population.
Sample surveys are able to provide useful demographic and health profiles of local populations. However, various parameters being measured and their distribution within the sampling unit of interest may not all be best represented by a particular sampling method. It is likely therefore that compromises may have to be made in choosing a sampling strategy, with costs, logistics the intended use of the data being important considerations.
Population Health Metrics 02/2008; 6:2. · 2.11 Impact Factor
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ABSTRACT: Less than 2% of scientific publications originate in low-income countries. Transfer of information from South to North and from South to South is grossly limited and hinders understanding of global health, while Northern-generated information fails to adequately address the needs of a Southern readership.
A survey of a new generation of health researchers from nine low-income countries was conducted using a combination of email questionnaires and face-to-face interviews. Data were gathered on personal experiences, use and aspirations regarding access and contribution to published research.
A total of 23 individuals from 9 countries responded. Preference for journal use over textbooks was apparent, however a preference for print over online formats was described among African respondents compared to respondents from other areas. Almost all respondents (96%) described ambition to publish in international journals, but cited English language as a significant barrier.
The desire to contribute to and utilise contemporary scientific debate appears to be strong among study respondents. However, longstanding barriers remain in place and innovative thinking and new publishing models are required to overcome them.
Global Health Action 01/2008; 1. · 1.27 Impact Factor
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Edward Fottrell,
Peter Byass,
Thomas W Ouedraogo,
Cecile Tamini,
Adjima Gbangou,
Issiaka Sombié,
Ulf Högberg,
Karen H Witten,
Sohinee Bhattacharya,
Teklay Desta,
Sylvia Deganus,
Janet Tornui,
Ann E Fitzmaurice,
Nicolas Meda,
Wendy J Graham
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ABSTRACT: Substantial reductions in maternal mortality are called for in Millennium Development Goal 5 (MDG-5), thus assuming that maternal mortality is measurable. A key difficulty is attributing causes of death for the many women who die unaided in developing countries. Verbal autopsy (VA) can elicit circumstances of death, but data need to be interpreted reliably and consistently to serve as global indicators. Recent developments in probabilistic modelling of VA interpretation are adapted and assessed here for the specific circumstances of pregnancy-related death.
A preliminary version of the InterVA-M probabilistic VA interpretation model was developed and refined with adult female VA data from several sources, and then assessed against 258 additional VA interviews from Burkina Faso. Likely causes of death produced by the model were compared with causes previously determined by local physicians. Distinction was made between free-text and closed-question data in the VA interviews, to assess the added value of free-text material on the model's output.
Following rationalisation between the model and physician interpretations, cause-specific mortality fractions were broadly similar. Case-by-case agreement between the model and any of the reviewing physicians reached approximately 60%, rising to approximately 80% when cases with a discrepancy were reviewed by an additional physician. Cardiovascular disease and malaria showed the largest differences between the methods, and the attribution of infections related to pregnancy also varied. The model estimated 30% of deaths to be pregnancy-related, of which half were due to direct causes. Data derived from free-text made no appreciable difference.
InterVA-M represents a potentially valuable new tool for measuring maternal mortality in an efficient, consistent and standardised way. Further development, refinement and validation are planned. It could become a routine tool in research and service settings where levels and changes in pregnancy-related deaths need to be measured, for example in assessing progress towards MDG-5.
Population Health Metrics 02/2007; 5:1. · 2.11 Impact Factor
