One hundred and seven women participated in a clinical study of an age-stratified random sample of sewing machine operators compared to a group of auxiliary nurses and home helpers. Four groups, according to years of being a sewing machine operator, consisted of: (controls) 25; (0-7 years) 21; (8-15 years) 25; and (more than 15 years) 36. The numbers of the main clinical diagnoses in the four groups were: cervicobrachial fibromyalgia (myofascial pain syndrome) 2, 4, 11, 24; cervical syndrome 0, 1, 3, 10; and rotator cuff syndrome 1, 1, 6, 11. The observed exposure-response relationship between clinical outcomes and years as a sewing machine operator was maintained when adjusting for current exposure to musculoskeletal strain and other potential confounders. Muscle palpation proved to be a reproducible examination with kappa values around 0.70.