Evaluation of symptom surveys for occupational musculoskeletal disorders

Symptom surveys have been used extensively as part of workplace ergonomic screening programs and epidemiologic assessments of musculoskeletal disorders in groups of workers. This paper examines the reliability and validity of two musculoskeletal symptom surveys, the Nordic Musculoskeletal Questionnaire (NMQ) and a survey used in conjunction with epidemiologic assessments by the National Institute for Occupational Safety and Health (NIOSH). Journal articles assessing the validity and reliability of the NMQ were reviewed. A retrospective assessment combining two NIOSH cohorts with a total of 852 workers assessed the reliability and validity of that survey. Reliability was assessed through test-retest methods and interitem correlations between similar questions. Validity was assessed by comparison with results from physical examination assessments of workers and self-reports of workers seeking medical care. Both reliability and validity were found to be acceptable for the purposes of workplace ergonomics programs. Implications for use of these surveys for prevention and treatment outcomes research are discussed.