Ecological studies: a key tool for public health

Abstract

Ecological studies (ES) are frequently analyzed with a skeptical attitude by researchers, who consider that the associations obtained in individual-level studies present a higher grade of scientific evidence than those referred to in population studies. Furthermore, it is argued that ES are only used to generate or test etiological hypotheses. Howe-ver, ES are a useful alternative for addressing contextual determinants since grouped variables provide information on attributes that are not captured by individual variables. This particularity facilitates the incorporation of ES in multilevel or contextual studies of great utility in public health. The purpose of this paper is based on these foundations, in which the present and future challenges and opportunities of ES as a key tool for the fulfillment of public health functions are pointed out.