The Global Prevalence of Noise Induced Hearing Impairment Among Industrial Workers: A Systematic Review and Meta-Analysis.

Noise is one of the harmful health factors in industrial sites. Hearing impairments are one of the most common occupational diseases in a wide range of industries. The aim of this study is to determine the general prevalence of noise-induced hearing disorders among industrial workers and to homogenize the results of different studies in this field. In this systematic review and meta-analysis study, the keywords of Occupational Noise, Hearing Impairment, Workers, Industry in Science Direct, PubMed, Scopus, Web of Science and Google Scholar databases without any lower time limit and until March 2022. Details of the identified studies were then transferred into the EndNote reference management software. Subsequently, duplicate studies were eliminated, and the remaining studies were evaluated in accordance with the inclusion and exclusion criteria and through the three remaining phases of PRISMA i.e., screening, eligibility, and inclusion. To analyze the eligible studies, the random effects model was used, and the heterogeneity of the studies was assessed using the I index. In a review of 69 studies with a sample size of 3,552,888 people, the overall prevalence of hearing impairment among industrial workers was 28.8% (95% CI 26.2%-31.6%). The highest prevalence of hearing impairments was reported among agricultural and fishery workers with 45.7% (95% CI 35.1%-56.7%), and the highest prevalence of hearing impairment among industrial workers was found in the continent of Africa with 46.2% (95% CI 37.4%-55.2%). Due to the higher prevalence of hearing impairments among men, the elderly and in developing countries, it is necessary to establish pertinent laws and regulations in order for workers to use appropriate personal protective equipment (PPE) and mandate employers to provide hearing protection programs.