[Evaluative designs in public health: methodological considerations].

Evaluation of public health interventions poses numerous methodological challenges. Randomization of individuals is not always feasible and interventions are usually composed of multiple factors. To face these challenges, certain elements, such as the selection of the most appropriate design and the use of a statistical analysis that includes potential confounders, are essential. The objective of this article was to describe the most frequently used designs in the evaluation of public health interventions (policies, programs or campaigns). The characteristics, strengths and weaknesses of each of these evaluative designs are described. Additionally, a brief explanation of the most commonly used statistical analysis in each of these designs is provided.