Ecological models revisited: their uses and evolution in health promotion over two decades.

Since the 1980s, ecological models of health promotion have generated a great deal of enthusiasm among researchers and interventionists. These models emerged from conceptual developments in other fields, and only selected elements of the ecological approach have been integrated into them. In this article, we describe the tenets of the ecological approach and highlight those aspects that have been integrated into ecological models used in health promotion. We also analyze how ecological models have been applied to the study of two important public health issues, namely physical activity promotion and the increased consumption of fruits and vegetables, by conducting an archival study of published research. Finally, we make a statement regarding the usefulness of ecological models for research and practice and propose recommendations for future research, program planning, and evaluation.