Search

International audience; Background : Many cities in developing countries experience an unplanned and rapid growth. Several studies have shown that the irregular urbanization and equipment of cities produce different health risks and uneven exposure to specific diseases. Consequently, health surveys within cities should be carried out at the micro-local scale and sampling methods should try to capture this urban diversity. Methods : This article describes the methodology used to develop a multi-stage sampling protocol to select a population for a demographic survey that investigates health disparities in the medium-sized city of Bobo-Dioulasso, Burkina Faso. It is based on the characterization of Bobo-Dioulasso city typology by taking into account the city heterogeneity, as determined by analysis of the built environment and of the distribution of urban infrastructures, such as healthcare structures or even water fountains, by photo-interpretation of aerial photographs and satellite images. Principal component analysis and hierarchical ascendant classification were then used to generate the city typology.Results : Five groups of spaces with specific profiles were identified according to a set of variables which could be considered as proxy indicators of health status. Within these five groups, four sub-spaces were randomly selected for the study. We were then able to survey 1045 households in all the selected sub-spaces. The pertinence of this approach is discussed regarding to classical sampling as random walk method for example. Conclusion : This urban space typology allowed to select a population living in areas representative of the uneven urbanization process, and to characterize its health status in regards to several indicators (nutritional status, communicable and non-communicable diseases, and anaemia). Although this method should be validated and compared with more established methods, it appears as an alternative in developing countries where geographic and population data are scarce.

L'urbanisation dans les pays du sud expose les territoires urbains à des changements démographiques, économiques, sociaux et environnementaux qui renouvèlent les enjeux de santé. Au Burkina Faso, la politique sanitaire a pour but de rapprocher les populations des équipements de soins. Elle s'appuie sur de nouveaux découpages, les districts sanitaires et les communes, responsables depuis la communalisation intégrale, des structures de soins de base. La répartition de l'offre de soins à Bobo-Dioulasso, seconde ville du Burkina Faso, est observée en lien avec la croissance urbaine. A partir de la géolocalisation des équipements, leur répartition spatiale est étudiée : selon des ellipses de dispersion pour les périodes de création, selon la méthode du plus proche voisin et de l'indice de Ripley pour le statut. A la dispersion spatiale des structures publiques, guidée par la politique de soins, s'oppose la concentration spatiale du privé. Malgré les rythmes de création différents, l'équipement ne semble pas se faire en adéquation avec le rythme de croissance urbaine.