Comprehensive evaluation of Salud Escolar a health school program in Mexico: Rationale, design and methods.

The prevalence of obesity and overweight in Mexican children and adolescents is high (greater than 30%) and lifestyle behaviors are far from achieving health recommendations. Salud Escolar is a complex cross-sectoral multi-level policy-based program in Mexico aiming to support schoolchildren healthy behaviors. We describe the rationale, design and methods for the comprehensive evaluation of Salud Escolar during its first phase of implementation. Using a mixed-methods approach and the logic model of Salud Escolar as a guide, a comprehensive evaluation involving 3 types of evaluations was designed: 1) A design evaluation before program implementation, to determine the consistency between the design of Salud Escolar and the problem to be addressed (i.e., childhood obesity), 2) An implementation evaluation to assess potential execution bottlenecks, and 3) An outcomes evaluation, to measure short-term (i.e., knowledge, attitudes and practices related to healthy eating, drinking plain water and doing regular physical activity) and intermediate outcomes (i.e., fruit and vegetable intake, water consumption and daily moderate to vigorous physical activity). This evaluation will provide essential knowledge about program design and implementation processes, which are vital for drawing robust conclusions about the effectiveness of the program. Results and lessons learned from this comprehensive evaluation will provide evidence to improve Salud Escolar program and facilitate its upscaling process and may provide relevant information for school-based programs in other places sharing socio-contextual conditions.