Depression is a common health problem in children and adolescents. Exercise is one possible treatment for depression. We are planning an update of the Cochrane Review 'Exercise in prevention and treatment of anxiety and depression among children and young people', published in 2006. Before starting the review process, it is important to map existing reviews to avoid waste in research. Through a systematic search of the literature, we identified four previous reviews on physical activity for depression.
To identify potential overlaps in existing reviews on exercise for depression in children and adolescents.
We explored the rationale for conducting the four reviews by comparing the publication dates and investigating to what extent the review authors referred to each other's work. We also explored potential overlap between the reviews by comparing the inclusion and exclusion criteria and entered this into a chart. We extracted the review authors' conclusions about the estimated treatment effects.
All four systematic reviews refer to the previously published reviews. Satisfactory reasons are given for conducting another review.
The reviews included different studies. Some studies are included in several of the reviews, while other studies are included in only one. The main reason for this was the different PICOs (participants, interventions, comparisons and outcomes), particularly regarding the population. Some of the reviews only included studies where the participants had been diagnosed with depression, while other reviews also included studies in general populations.
The review authors conclusions are comparable, stating that exercise in this population is likely to be effective for depression. However, due to the small studies and their methodological weaknesses, the results are uncertain.
We identified previous reviews and explored the reasons for multiple reviews on the same subject within a short period. The reported reasons for conducting a new review were well-reasoned. Although the PICOs differed, the review authors' conclusions about effects were similar.