Table 2. ONIHL prevalence among the participants (n = 312).
* Statistically significant. One expected cell count was <5 (minimum expected count = 4.62); therefore, statistical significance was additionally verified using a Monte Carlo exact test (p < 0.001).
CTC, crushing-tearing-curling; ONIHL, occupational noise-induced hearing loss
| Job station | Noise level exposure, dBA | ONIHL present | ONIHL absent | ONIHL prevalence, n/N (%) | 95% CI | Chi-square value | p-value | ||||
| Range | Leq, 8h, dBA | Median (IQR) | Frequency | Percentage | Frequency | Percentage | |||||
| CTC room | 82-86 | 85.3 | 85.2 (84.0-86.9) | 60 | 66.7 | 74 | 33.3 | 60/134 (44.8) | 36.6-53.2 | 37.434 | <0.001* |
| Withering room | 70-84 | 80.7 | 79.8 (77.8-81.6) | 11 | 12.2 | 28 | 12.6 | 11/39 (28.2) | 16.5-43.8 | ||
| Drying room | 66-74 | 72.8 | 73.8 (72.2-74.2) | 3 | 3.3 | 26 | 11.7 | 3/29 (10.3) | 3.6-26.4 | ||
| Sorting room | 62-74 | 66.7 | 66.6 (66.4-67.1) | 2 | 2.2 | 24 | 10.8 | 2/26 (7.7) | 2.1-24.1 | ||
| Packing room | 60-74 | 66.5 | 66.8 (66.1-67.2) | 4 | 4.4 | 25 | 11.3 | 4/29 (13.8) | 5.5-30.6 | ||
| Maintenance staff | 55-93 | 85.1 | 83.1 (81.8-88.9) | 6 | 6.7 | 10 | 4.5 | 6/16 (37.5) | 18.5-61.4 | ||
| Administrative office staff | 50-66 | 60.6 | 62.6 (62.1-63.4) | 4 | 4.4 | 35 | 15.8 | 4/39 (10.2) | 4.1-23.6 | ||
| Total | - | - | - | 90 | 100 | 222 | 100 | 90/312 (28.8) | 24.1-34.1 | ||