Comparison of criteria for significant threshold shift in workplace hearing conservation programs.

Abstract

The National Institute for Occupational Safety and Health (NIOSH) recommended that the Standard Threshold Shift (STS) be replaced as the sentinel indicator of hearing loss in workplace audiometric surveillance programs. We conducted a retrospective cohort study of 1220 workers followed for eight consecutive years in the hearing conservation program at the Hanford nuclear facility, to evaluate the relative accuracy of eight candidate threshold-shift criteria for detecting hearing loss over time, using two evaluation methods and comparing to NIOSH findings. The NIOSH-recommended criterion was one of the better criteria. However, the differences between better criteria were less evident using a different evaluation method than the one described by NIOSH. Also, when we compared our findings with those underlying the NIOSH recommendation, the between-database differences were large enough that the smaller between-criteria differences may have limited importance.