title: An evaluation of hearing conservation program--a five-year longitudinal study.
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001299:Audiometry; D001309:Auditory Threshold; D003691:Delaware; D005069:Evaluation Studies as Topic; D006317:Hearing Loss, Noise-Induced / Q000517:prevention & control*; D006320:Hearing Tests; D006801:Humans; D008297:Male; D008452:Maximum Allowable Concentration; D008875:Middle Aged; D009622:Noise / Q000517:prevention & control*; D009784:Occupational Diseases / Q000517:prevention & control; D011446:Prospective Studies; D011482:Protective Devices; D013997:Time Factors