Comparison 11. Earmuffs vs earplugs (long‐term).

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Hearing loss change over 3 years (4 kHz / STS)	2		OR (Random, 95% CI)	Subtotals only
1.1 High noise exposure > 89 dB(A)	2		OR (Random, 95% CI)	0.80 [0.63, 1.03]
1.2 Low noise exposure < 89 dB(A)	2		OR (Random, 95% CI)	2.65 [0.40, 17.52]