Comparison 1. Sleep quality: listening to music versus control ‐ Pittsburgh Sleep Quality Index (PSQI) ‐ global score.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Sleep quality: Pittsburgh Sleep Quality Index (PSQI) ‐ immediately post‐treatment	5	264	Mean Difference (IV, Random, 95% CI)	‐2.80 [‐3.42, ‐2.17]
2 Subgroup (PSQI) by music selection ‐ immediatly post‐treatment	5		Mean Difference (IV, Random, 95% CI)	Subtotals only
2.1 Researcher‐selected music	3	144	Mean Difference (IV, Random, 95% CI)	‐2.42 [‐3.24, ‐1.60]
2.2 Participant‐selected music (choice among researcher pre‐selected music)	2	130	Mean Difference (IV, Random, 95% CI)	‐3.35 [‐4.28, ‐2.42]
3 Subgroup (PSQI) by relaxation instructions ‐ immediately post‐treatment	5		Mean Difference (IV, Random, 95% CI)	Subtotals only
3.1 Music listening alone	3	149	Mean Difference (IV, Random, 95% CI)	‐2.85 [‐3.92, ‐1.78]
3.2 Music listening and relaxation instructions	2	125	Mean Difference (IV, Random, 95% CI)	‐2.64 [‐3.74, ‐1.54]