The study aimed to compare the validity of two questionnaires (NIOSH- and Nordic-style) which are used for the screening and surveillance of neck and upper extremity work-related musculoskeletal disorders. To evaluate the validity, clinical examination was used as the reference.

Two types of questionnaire were filled out by 208 workers from three different plants in Incheon, Korea. Workers underwent clinical examination by three occupational physicians. The presence of a symptom or sign in at least one body region was regarded as positive in both results of questionnaire and case definition using clinical examination. Validity was evaluated by sensitivity, specificity, positive predictive value, negative predictive value and agreement (Kappa coefficient). For the Nordic-style questionnaire, the sum of the symptom scores was used to yield the ROC curve.

The results of the NIOSH-style questionnaire were sensitivity 59.5%, specificity 68.0%, positive predictive value 68.0%, negative predictive value 59.5%, and Kappa coefficient 0.27(95% confidence interval [CI]=0.14~0.40). The results of the Nordic-style questionnaire were sensitivity 73.9%, specificity 68.0%, positive predictive value 72.6%, negative predictive value 69.5%, and Kappa coefficient 0.42 (95% CI=0.30~0.54). For the Nordic-style questionnaire, sensitivity was 72.1% and specificity was 70.1% based on the sum of the symptom scores > or =2.

Both questionnaires demonstrated appropriate validity for the screening and surveillance of work-related musculoskeletal disorders. The selection of questionnaire may depend on the purpose of investigation and characteristics of the work place.