Association of neck and shoulder complaints with psychosocial factors measured by the Copenhagen Psychosocial Questionnaire

Introduction
The Copenhagen Psychosocial Questionnaire (COPSOQ) is a tool to assess all important aspects of the psychosocial work environment, stressors as well as resources. Although the COPSOQ is theory-based, it is not attached to one single theory, and was shown to be a reliable instrument. This study aimed to evaluate the influence of occupational psychosocial factors assessed by the COPSOQ on the presence of neck and shoulder complaints (NSC).

Methods
1529 subjects employed in different public institutions were asked to participate in a cross-sectional questionnaire study. 1279 subjects (83.6%) filled out the questionnaire; 37 of them suffered from earlier neck or shoulder trauma and were excluded from the study population. The dependent outcome variable was the one-year prevalence of NSC. Following COPSOQ variables were considered in the analyses: quantitative demands, work pace, cognitive demands, emotional demands, demands for hiding emotions, influence at work, possibilities for development, variation of work, meaning of work, commitment to the workplace, predictability, reward/recognition, role clarity, role conflicts, quality of leadership, social support from supervisor, social support from colleagues, social community at work, job insecurity, vertical trust, horizontal trust, justice and respect, degrees of freedom. Following variables were considered as well: age, gender, physical strain, number of children at home, taking care of disabled people. Multivariate logistic regression analysis was performed to assess the impact of psychosocial work factors on the presence of NSC.

Results
Following variables were significantly associated with the presence of NSC in the multivariate analysis: gender (women vs. men, OR 2.08), quantitative demands (OR 1.15), emotional demands (OR 1.07), influence at work (OR 0.91), quality of leadership (OR 0.91).

Discussion
The COPSOQ enabled to identify relevant psychosocial factors associated with NSC. This result indicated the importance of considering a broad range of psychosocial factors not attached to a single psychosocial strain model.