Setting priorities for environmental sanitation interventions based on epidemiological criteria: a Brazilian study

The present study addresses the use of analytical epidemiologic approaches to subsidize the establishment of priorities in environmental sanitation interventions. An epidemiological investigation was carried out in 1993 in the urban area of Betim, a southeast Brazilian City of 160,000 inhabitants. The case-control 'inclusive' (or case-cohort) design, with a sample of 997 cases and 999 controls, was employed. Cases were defined as children of less than five years of age presenting diarrhoea episodes, while controls were randomly selected among children of the same age, living in the study area. After logistic regression adjustment, 11 of several exposure variables analysed were significantly associated with diarrhoea. Four different criteria, using as risk measures the relative risk, the attributable risk, the standardized coefficient of the logistic regression and the cost standardized coefficient, were used in order to define intervention priorities.