The course of complaints of arm, neck and/or shoulder: a cohort study in a university population participating in work or study.

Background: Not much is known about the characteristics, course and prognosis of complaints of arm, neck and/or shoulder that have not been caused by a trauma or systemic disease (CANS), in a screened population. This study aims to: (1) describe personal and complaint characteristics in a screened population; (2) describe the course during one-year follow-up, in terms of the three different domains of functioning of the International Classification of Functioning, Disability and Health (ICF); and (3) to explore prognostic factors for the different domains of functioning at one-year follow-up. Additionally, this study aims to investigate the manifestation of selection effects (i.e. tertiary selection effects), in order to understand their impact on the interpretation of results.

Methods: A cross-sectional survey was conducted in a university population. Survey respondents who fulfilled eligibility criteria were asked to participate in a longitudinal cohort study. The course of CANS was assessed in terms of the three ICF domains of functioning. Possible prognostic factors across the different components of the ICF were selected to investigate their influence on outcome at one-year follow-up. Non-response analyses were performed to investigate the presence of tertiary selection effects.

Results: The results revealed a population with relatively mild complaints at baseline, and a relatively stable course during follow-up. Because of the small change in scores between baseline and follow-up measurements, examination of prognostic factors was not feasible. The results of the non-response analyses revealed some indications for the potential presence of tertiary selection effects, which may imply that the results obtained are a slight overestimation of the true results.

Conclusion: The results of this study demonstrate mild complaints at baseline and an overall stable course during one-year follow-up. Since selection effects cannot be ruled out, the true course might possibly be somewhat less favourable than our results suggest.