Defining, illustrating and reflecting on logic analysis with an example from a professional development program

•Logic analysis is a specific evaluation approach that can be used to test the plausibility of a program's intervention theory.•This paper presents a logic analysis of the Health Promotion Laboratory program, a public health professional development program.•The logic analysis helped to identify the program's strengths and weaknesses.•Logic analysis has proven to be a useful method for strengthening a program's theoretical basis and facilitating program improvement.

Program designers and evaluators should make a point of testing the validity of a program's intervention theory before investing either in implementation or in any type of evaluation. In this context, logic analysis can be a particularly useful option, since it can be used to test the plausibility of a program's intervention theory using scientific knowledge. Professional development in public health is one field among several that would truly benefit from logic analysis, as it appears to be generally lacking in theorization and evaluation. This article presents the application of this analysis method to an innovative public health professional development program, the Health Promotion Laboratory. More specifically, this paper aims to (1) define the logic analysis approach and differentiate it from similar evaluative methods; (2) illustrate the application of this method by a concrete example (logic analysis of a professional development program); and (3) reflect on the requirements of each phase of logic analysis, as well as on the advantages and disadvantages of such an evaluation method. Using logic analysis to evaluate the Health Promotion Laboratory showed that, generally speaking, the program's intervention theory appeared to have been well designed. By testing and critically discussing logic analysis, this article also contributes to further improving and clarifying the method.