Effects of transient threshold shift and ambient noise on sensitivity and specificity of first screening of special health examination for noise

Won, Jong Uk; Bang, Moon Kyoo; Song, Joong Ho; Jeong, Sedn Ah; Song, Jae Suk; Roh, Jaehoon

Abstract

OBJECT: This study was performed to increase the sensitivity and specificity for screening the examinee of second hearing test.
METHODS
Study subjects were 219 workers who exposed more than average 80dB. They were taken the hearing test two times, before noise exposure and at 1 hour to 4 hours after worksite noise exposure. To investigate the ambient noise workers who were taken the hearing test in the test room which ambient noise was less than 45dB were classified Group I and the others were classified Group E. To calculate the sensitivity and specificity we made it gold standard whether worker had noise induced hearing loss.
RESULTS
Difference of hearing loss between before and after noise exposure for left and right ear was 11. 4 dB and 11. 7 dB respectively at 500 Hz, 8. 7 dB and 9. 6 dB at 1, 000 Hz, 6. 3 dB and 6. 9 dB at 2, 000 Hz and 6. 9 dB and 7. 4 dB at 4, 000 Hz in Group I. That for left ear and right ear was 5.8 dB and 4.9 dB at 500 Hz respectively, 5.4 dB and 6.4 dB at 1,000 Hz, 6.3 dB and 5.3 dB at 2,000 Hz, and 5.5 dB and 5.8 dB at 4,000 Hz in Group E. The sensitivity was 100 in both Groups and the specificity was increased to 58. 3 and 71. 8 in Group I and Group 3 respectively until 10 dB was deducted from hearing level at 1, 000 Hz and 4, 000 Hz.
CONCLUSION
When the screening hearing test was performed at worksite, we might deduct 10 dB from measured hearing level to increase the specificity without reduction of sensitivity.