title: Occupational noise exposure and age correction: the problem of selection bias.
abstract: Selection bias often invalidates conclusions about populations based on clinical convenience samples. A recent paper in this journal makes two surprising assertions about noise-induced permanent threshold shift (NIPTS): first, that there is more NIPTS at 2 kHz than at higher frequencies; second, that NIPTS declines with advancing age. Neither assertion can be supported with the data presented, which were obtained from a clinical sample; both are consistent with the hypothesis that people who choose to attend an audiology clinic have worse hearing, especially at 2 kHz, than people of the same age and gender who choose not to attend.
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, University of Texas, Health Science Center at San Antonio, San Antonio, TX 78229, USA. dobie@uthscsa.edu
authors.forename: Robert A
authors.initials: RA
authors.lastname: Dobie
mesh_terms: D000367:Age Factors; D000375:Aging; D015982:Bias; D015340:Epidemiologic Research Design; D006317:Hearing Loss, Noise-Induced / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D009623:Noise, Occupational / Q000009:adverse effects*; D018570:Risk Assessment; D014481:United States / Q000453:epidemiology