[Criteria for chronification of diseases of the musculoskeletal system]

Musculoskeletal disorders, especially low back pain, are responsible for most of the days of work absenteeism in western industrial countries. Part of these disorders will get chronic in course of time. The question is, which criteria could be used to identify persons with chronic complaints. In the present study were selected persons with degenerative disorders and persons with idiopathic low back pain. As criterion for chronic complaints we used accumulated days of work absenteeism in two different ways. The first method identified persons with chronic complaints by percentiles of days of work absenteeism in 1990 leading to four groups (Q1-4). The second method used as the relevant criteria the number of years with days of work absenteeism for rheumatic complaints identifying three groups (Q1-3). Both suggested methods were compared for plausibility and validity with relevant parameters (progress of days of work absenteeism, sociodemographic variables, health status). Any method could identify persons with chronic disorders, so we propose to integrate subjective data to get a more valid index.