Do animal-assisted activities effectively treat depression? A meta-analysis

We conducted a meta-analysis to determine the effectiveness of animal-assisted activities (AAA) and animal-assisted therapy (AAT) for reducing depressive symptoms in humans. To be included in the meta-analysis, studies had to demonstrate random assignment, include a comparison/control group, use AAA or AAT, use a self-report measure of depression, and report sufficient information to calculate effect sizes, a statistical standardization of the strength of a treatment effect. Five studies were identified for analysis. The aggregate effect size for these studies was of medium magnitude and statistically significant, indicating that AAA/AAT are associated with fewer depressive symptoms. This analysis revealed gaps in the research on AAA/AAT, which we attempted to identify in order to better understand the factors that make AAA and AAT effective at reducing depression.