The commonest rheumatic complaints of over six weeks' duration in a twelve-month period in a defined Swedish population. Prevalences and relationships.

In 900 randomly selected individuals, 50-70 years old, we examined the prevalence over the preceding 12-month period of rheumatic complaints of more than 6 weeks' duration. We found them to represent a major health problem, with an overall prevalence of 37.8%, the predominant diagnoses being subacromial shoulder pain (6.7%), neck pain (6.5%), low back pain (6.3%), osteo-arthrosis (8.5%), and arthralgia (4.9%). With a prevalence of 1.0%, primary fibromyalgia was as common as rheumatoid arthritis (0.7%) and other chronic arthritides (1.1%). The prevalences of the different diagnoses were higher among participants whose data were obtained from personal investigation by a physician than among non-participants where data were obtained by interview, letter, and scrutiny of case records. The odds ratio from incurring more than one rheumatic disease was higher for subacromial shoulder pain and lowest for arthralgia and osteo-arthrosis.