Classification proposal of the different types of descriptive epidemiological studies

Abstract

Descriptive epidemiological studies are relevant for public health care services.  Nevertheless, their nomenclature and classification are faulty.  We reviewed textbooks on epidemiology available for a careful review of chapters on descriptive epidemiology and study designs, 19 from foreign literature and 6 from Brazil.  In 11 books, authors do not even take the category of descriptive studies into consideration and only include analytic designs.  Twelve foreign textbooks and two from Brazil include specific descriptive studies although not always mentioning a category with this name.  We propose a classification based on the research question to which they are responding; it includes three studies to be conducted on clinical settings: case report, case series, clinical cohort; and four at population / community level: study of prevalence, study of incidence (cohort), descriptive-ecological and study of intervention before- and-after.  We discuss potential uses, implementation of novel data analysis methods and their importance on surveillance.