Risk factors for arm-wrist-hand and neck-shoulder symptoms among office workers : a longitudinal perspective

In this thesis the association was examined between the duration of computer use at work and the onset of arm-wrist-hand and neck-shoulder symptoms. A prospective cohort study among 1951 office workers was performed with a follow-up period of 2 years. Outcome was assessed every three months by questionnaire. Cases were identified based on the transition within 3 months of no, irregular or "minor" symptoms to regular or prolonged symptoms accompanied with a pain intensity exceeding 6 on a Von Korff scale 20 for worst symptoms or medication use to control symptoms. The results showed that self-reported exposure data were positively associated with the onset of both neck-shoulder and arm-wrist-hand symptoms. Registered exposure data were not associated with the outcomes. In conclusion, the findings of this prospective cohort study challenges the existence of a causal link between the duration of computer use at work and the onset of arm-wrist-hand and neck-shoulder symptoms, based on the absence of an association between the registered duration of computer use at work and the onset of arm-wrist-hand and neck-shoulder symptoms. The positive association between the self-reported duration of computer use at work and the onset of arm-wrist-hand and neck-shoulder symptoms could not be explained satisfactory