Dr. George Howard, professor in the department of biostatistics, and Dr. Virginia J. Howard, professor in the department of epidemiology both work at the UAB School of Public Health. They serve as principal investigator and co-principal investigator (respectively) of the REasons for Geographic And Racial Differences in Stroke (REGARDS) Study, a longitudinal cohort study of 30,239 African American and white participants in 48 states.
[Photo: Dr. George Howard (left) and Dr. Virginia J. Howard]
In their recent publication in International Journal of Stroke, they note that observational epidemiological studies have the dual goals of measuring disease burden and assessing the association between exposures and outcomes. This report focuses on the first of these goals and provides an overview of design considerations of commonly used approaches, specifically community surveillance studies, cross-sectional studies, and longitudinal cohort studies. Each of these designs has strengths and weaknesses, with no study design being superior in all cases.
The purpose of this paper is to provide an introduction to the approaches and methods to assess the burden of disease and outcomes with an application to stroke with other texts providing detail to enrich the points made briefly herein.
They conclude that there are several alternative approaches for observational studies to assess the burden of disease, each with advantages and disadvantages. If the primary goal is to assess burden, then the community surveillance study is a powerful design. However, if the primary goal is to assess the relationships between exposures and outcomes, the cohort study is preferred (or the cross-sectional study if there is a focus on study time and cost). There is no best design, rather the information from these studies should be considered as complementary, and together, they can provide a rich description of the burden and outcome of stroke.