highly significantP < 0.001
Hearing threshold differences across 0.25–4 kHz were highly significant among occupational groups (all P < 0.001, η 2 = 0.43–0.48), exceeding Cohen’s large-effect criterion (>0.14).[ 13 ] This confirmed a strong link between occupational exposure and hearing loss, consistent with Blair et al .[ 14 ] The hearing loss of fighter and helicopter pilots showed a ‘high-frequency priority’, with maximal threshold elevation at 3–4 kHz, aligning with their respective noise spectra (3–6 kHz for fighters; 2–5 kHz for helicopters).[ 15 ] This correspondence suggests that the spectral composition of noise determines the hearing loss pattern.