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Noise-induced hearing loss among quarry workers in a north-eastern state of malaysia: a study on knowledge, attitude
Ahmad Filza Ismail1, Aziah Daud, Zaliha Ismail
1Department of Community Medicine, School of Medical Sciences, Health Campus 16150, Kubang Kerian, Kelantan, Malaysia.
Objectives:
Noise is known to be one of the environmental and occupational hazards listed in the Factory and Machinery Act 1967. Quarries with loud deafening sounds from trucks and machineries pose the risk of noise-induced hearing loss to workers. This study was designed to assess the knowledge, attitude and practice towards noise-induced hearing loss and to determine the prevalence of noise-induced hearing loss and its associated factors among quarry workers in a north-eastern state of Malaysia.
Methods:
A cross-sectional study was conducted at six quarries in a north-eastern state of Malaysia, with 97 consented respondents who answered a validated version of a questionnaire and underwent pure tone audiogram. The respondents were male, aged between 18 to 50 years, working in the quarry area for at least 6-months duration with no family history of ear diseases.
Results:
The mean percentage scores of knowledge, attitude and practice were 44 (11), 70 (10) and 28 (16) percent, respectively. The prevalence of noise-induced hearing loss was found to be 57 (95% CI: 47, 67) with 46 (84%) having mild and moderate noise-induced hearing loss, and 34 (62%) involved both ears. Multiple logistic regressions showed that age and practice score were the associated factors with odd ratios of 1.1 (95% CI: 1.1, 1.2; p<0.001) and 0.9 (95% CI: 0.8, 1.0; p=0.008), respectively.
Conclusion:
The knowledge, attitude and practice scores of the respondents were poor and the high prevalence of noise-induced hearing loss was contributed by factors such as poor practice and old age.
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