Strengths and Limitations
This study has several strengths. To our knowledge, it is one of the first cluster randomized trials to test the effect of a multilevel physical activity intervention in older adults from developing countries, so our study narrows this knowledge gap. Furthermore, the intervention was based on a socioecological model, which enabled the intervention to be more effective and scalable. In addition, previous studies have revealed that individuals with low income are rarely involved in physical activity intervention programs.This study also has several limitations. First, physical activity level was assessed by self-report and may have been subject to recall bias. However, the PASE scores obtained from the reliable and valid PASE questionnaire were highly consistent with the objective assessment of physical activity.