In conjunction with audiometric testing, OAE testing can be completed to determine changes in the responses. Studies have found that exposure to noise can cause a decline in OAE responses. In a study, industrial workers who were exposed to 84.5 dBA of noise were compared to workers who were exposed to 53.2 dBA of noise by considering hearing thresholds and OAEs before and after 5 days of work. This study revealed that hearing thresholds and OAE results were significantly lower among the workers who were exposed to higher levels of noise.
Perhaps the first sign that this book would be a let down were the typos throughout the pages (such as "hunbands" for husbands p 211, "sores" for scores p 104). The carelessness of the authors was reflected in the poor quality of the content and its presentation. This book lacked a coherent voice, and others have noted the contradictory statements found throughout its pages.