Challenges and Milestones of a Cohort Study in a Rural Area of South Africa: The Ellisras Longitudinal Study

Abstract

Health care practitioners seek to base decisions regarding disease management strategies on the best available evidence to improve the quality of life. This is especially true of resource-limited rural populations in Africa, where the ordinary person can often not even afford the most basic medical care. The purpose of this paper is to briefly explain the nature of a cohort study, its challenges and milestones within the African context, based on the Ellisras Longitudinal Study (ELS). A total of 2225 children, 550 pre-school (mean age of 4.4 ± 0.99 years) and 1675 primary school children (mean age of 8.0 ±1.11 years) were used at baseline, and were followed for the period 1996 to 2003 employing periodic surveys for data collection. A total of 1771 subjects, comprising of 489 pre-school children (mean age of 11.4 ± 0.96 years) and 1282 primary school children (mean age of 14.9 ± 1.11 years), were successfully followed up to November 2003. The migration or relocation of families from rural to urban areas or from one area to another within Lephalale; the naming of siblings in the family, children parenting the families, and long term financial commitment were among major challenges experienced in the ELS. In addition, the prevalence of hypertension and obesity was found to be low in this population, though malnutrition in terms of mild, moderate, and severe was extremely high. Over time, the development of fat among Lephalale girls was high compared to boys. Obtaining and applying research-based evidence could fulfill the goal of achieving optimal goals of educating the community about the best available strategies for better health for all.

Keywords: African Continent, Attrition Rate, Cohort Study, Cardiovascular Diseases, Hypertension, Malnutrition