Effectiveness of pre-operative clown intervention on psychological distress: A systematic review and meta-analysis

This study aims to provide an overview of the current knowledge available on the effectiveness of pre-operative clown intervention on psychological distress in children and parents.

PubMed, MEDLINE, Embase and PsycINFO databases were searched to identify relevant studies. Systematic review procedures were followed including a quality assessment. Meta-analysis of suitable studies was conducted.

Eight studies were included; six reported that clown intervention reduced children's pre-operative anxiety, while one found that children's pre-operative distress levels were unchanged. Two studies suggested that clown therapy decreased parents' state anxiety, while three others found inconsistent results. No differences were found on parents' trait anxiety score. Meta-analysis of the available data confirmed that clown intervention has a great effect to reduce children's pre-operative distress (six articles, 341 children, Hedges' g = 0.867, 95% confidence intervals: 0.374-1.360, P = 0.001), and also had a small-to-medium effect on reducing parents' state anxiety (five articles, 329 parents, Hedges' g = 0.338, 95% confidence intervals: 0.112-0.564, P = 0.003).

While significant variability existed between studies, the meta-analysis confirmed the effectiveness of pre-operative clown therapy on reducing psychological distress in children and parents. Larger randomised controlled trails and cross-cultural studies should be conducted to investigate the effectiveness of clown therapy in greater detail.