Psychometric properties of the readiness for return to work scale in inpatient occupational rehabilitation in Norway.

Aim: To investigate internal consistency and construct validity of the Readiness for return to work (RTW) scale in a sample participating in a Norwegian inpatient occupational rehabilitation program.

Methods: A cross-sectional study was conducted on baseline measures from a prospective cohort study evaluating a 5 days inpatient occupational rehabilitation program. The participants in the program were 18-67 years, on sickness absence or at risk of sickness absence (N = 193). The Readiness for RTW scale, sociodemographic-, work- and health-related questionnaires were answered by the participants on their first day in the program. Statistical analysis included exploratory factor analyses, reliability analyses and correlations with related instruments.

Results: In the scale for those not working (N = 124) two factors were found, representing (1) RTW inability and (2) RTW uncertainty. These factors corresponded to the precontemplation and contemplation stages in a previous Canadian study. The original prepared for action stages were not identified in this sample. In the scale for those working shortly before the program (N = 60) two factors were identified, representing (1) Uncertain work maintenance and (2) Proactive work maintenance, comparable to the stages in the Canadian study. The factors had satisfactory internal consistency (Cronbach's alpha >0.7), except for proactive work maintenance (Cronbach's alpha = 0.59). Expected relationships were found between the readiness for RTW stages and the pain stages of change, fear avoidance beliefs for work, subjective health complaints, decision control and coping at work.

Conclusion: Internal consistency and construct validity of the readiness for RTW stages found were satisfactory, except for proactive work maintenance. The results indicate that the construct of readiness for RTW may vary by culture and patient setting.