The Number Needed to Treat for Music as a Medicine against Perioperative Anxiety: A Systematic Review and Meta-Analysis.

Abstract

Music intervention is effective in reducing perioperative anxiety, which occurs in a majority of hospitalized surgical patients. A calculated Number Needed to Treat (NNT) provides an intuitive means of conveying the effectiveness of an intervention that can help clinicians decide whether or not to implement said intervention. This study aimed to calculate an NNT to provide extra context to help clinicians consider the implementation of music intervention. To calculate the NNT of music intervention for perioperative anxiety, a systematic review and meta-analysis were performed. A comprehensive literature search was conducted in Medline ALL, Embase, Web of Science Core Collection, Cochrane, CINAHL Plus, and PsycINFO from inception until April 14, 2025. Studies describing randomized controlled trials comparing the effect of perioperative music intervention on perioperative anxiety, measured with any validated tool, were included. The revised Cochrane risk-of-bias handbook was used to determine the quality of the included studies. The NNT was calculated with Furukawa's method, converting a calculated Cohen's d to an NNT. Twenty papers were included in the review and meta-analysis. All studies used either the Visual Analog Scale for Anxiety or the 6-item State-Trait Anxiety Index. Standardized mean difference of anxiety reduction after music interventions was -0.72 (95% confidence interval [CI], -0.92 to -0.53), which equals a moderate-to-large effect size. The NNT for perioperative music intervention is 4. This indicates that 4 patients need to listen to music perioperatively, to reduce the Visual Analog Scale for Anxiety for 1 patient by 12 mm, or the State-Trait Anxiety Index by 5.7 points. This meta-analysis shows that a relatively low number of patients need to be treated with music intervention to reduce perioperative anxiety with an effectiveness similar to benzodiazepines.