Table 2.
Prevalence of NIHL associated with complex noise versus Gaussian noise
| Author | Group | Type of factory | Population | Noise level (max or mean) (dB(A)) |
CNE(dB(A)·year) | Kurtosis (mean±SD) | NIHL (%) | HFNIHL prevalence | ||||||
| N | Age (years) | Exposure duration (years) | Male (%) | HFNIHL | SFNIHL | NID | OR | 95% CI | ||||||
| Liu62 | Gaussian | Clothing | 1421 | 32.8±6.9 | 3.6±2.1 | 79.9 | 93.4±5.0 | 99.1±8.2 | – | 9.2 | – | 6.8 | 0.83 | 0.61 to 1.11 |
| Complex | Hardware | 957 | 32.5±8.3 | 4.1±1.8 | 78.0 | 93.1±4.2 | 99.0±7.8 | – | 7.7 | – | 6.3 | |||
| Xie63 | Gaussian | Textile | 26 | 35.7±8.2 | 9.8±5.9 | 76.9 | 95.1±1.3 | 104.0±4.4 | – | 38.5 | 7.7 | – | 2.53 | 1.04 to 6.14 |
| Complex | Rolling | 98 | 37.4±6.5 | 9.9±7.4 | 84.7 | 94.9±4.0 | 103.5±6.3 | – | 61.2 | 17.4 | – | |||
| Zheng64 | Gaussian | Machinery | 399 | 33.6±9.9 | 11.6±8.6 | 70.2 | 100.0 | 96.8±6.0 | – | 56.6 | 25.8 | – | 2.94 | 2.06 to 4.19 |
| Complex | Machinery | 271 | 30.6±8.8 | 10.1±8.2 | 86.7 | 102.1 | 104.8±5.0 | – | 79.3 | 39.1 | – | |||
| Zhang65 | Gaussian | Machinery | 202 | – | – | 100.0 | 93.4±1.5 | – | – | 13.4 | – | 0.5 | 9.13 | 5.60 to 14.89 |
| Complex | Machinery | 212 | – | – | 100.0 | 92.7±1.0 | – | – | 58.5 | – | 6.1 | |||
| Zhao66 | Gaussian | Textile | 163 | 31.5±8.7 | 12.7±8.4 | 100.0 | 99.9±4.2 | 110.6±6.0 | 3.3±0.3 | 64.4 | – | – | 1.06 | 0.48 to 2.34 |
| Complex | Metal | 32 | 35.1±7.2 | 12.3±7.1 | 37.5 | 95.2±3.1 | 103.2±4.2 | 40.0±44.0 | 65.6 | – | – | |||
| Xie67 | Gaussian | Textile | 163 | 31.7±8.7 | 12.7±8.4 | 49.7 | 101.2±4.7 | 110.3±6.1 | 3.2±0.3 | 64.4 | – | – | 0.74 | 0.48 to 1.15 |
| Complex | Steel | 178 | 38.1±7.6 | 13.0±8.0 | 100 | 93.6±5.7 | 103.6±7.2 | 37.1±52.9 | 57.3 | – | – | |||
| Zhang68 | Gaussian | Pharmaceutical | 62 | 36.8±6.6 | – | 66.1 | 92.2±5.3 | 97.6±5.5 | – | 32.3 | – | – | 2.59 | 1.13 to 5.96 |
| Complex | Forging | 38 | 32.9±5.5 | – | 100.0 | 95.2±3.9 | 97.0±6.4 | – | 55.3 | – | – | |||
| Total | Gaussian | – | 2436 | 32.9±7.9 | 6.5±6.6 | 92.1 | 96.3±6.1 | 101.9±8.8 | 3.3±0.3 | 25.6 | 24.7 | 6.1 | 1.95 | 0.93 to 4.09 |
| Complex | – | 1786 | 33.2±8.5 | 6.7±6.1 | 67.8 | 94.0±4.8 | 103.3±6.5 | 33.0±51.7 | 34.5 | 33.3 | 6.2 | |||
CNE, cumulative noise exposure; dB(A), A-weighted decibels; HFNIHL, high-frequency noise-induced hearing loss; NID, noise-induced deafness;NIHL, noise-induced hearing loss; SFNIHL, speech-frequency noise-induced hearing loss.