Abstract
This meta-analysis was conducted to determine the effect of laughter therapy on anxiety. Randomized controlled clinical trials were reviewed on Google Scholar, PubMed, and ISI Web of Sciences databases. Four randomized controlled trials consisting of 157 participants were included in the meta-analysis. Hedge's g test statistics were used to show the common effect between the laughter therapy and control groups in the meta-analysis. Laughter therapy can decrease anxiety levels (standardized mean difference = -1.144; 95% CI, -1.950 to -0.338). Laughter therapy is an effective complementary method to decrease anxiety.