Beyond surveillance: methodologic considerations in analytic studies of agricultural injuries.

A major impediment to current efforts to lower the toll of injuries in agricultural workers is a fundamental lack of knowledge of the causes and risk factors associated with these injuries. Surveillance systems and other descriptive efforts can provide useful information on the scope and spectrum of agricultural injuries but can seldom identify specific factors, such as faulty machinery, risky behaviors, or particularly hazardous environments, which can be the focus of preventive efforts. Since few analytic epidemiologic studies of the causes of agricultural injuries have been conducted to date, a large number of focused, carefully designed studies, of both cohort and case-control design, will be needed to develop the information on which effective interventions can be based. This paper highlights certain methodologic barriers to effective analytic studies of agricultural injuries and suggests approaches to addressing these methodologic concerns.