Explaining the gender difference in sickness absence and testing the efficacy of a clinical intervention to promote return to work in women

Norwegian women have the highest sickness absence rate of all countries in the OECD, despite a good population health. The gender difference in sickness absence is relatively higher in Norway (about 70% higher in women than men) than in other OECD countries (about 50% higher). This gender difference represents a major concern in terms of health, wellbeing, and gender equality, and is largely unexplained in the research literature. There is no evidence for any intervention with merit to reduce or prevent the gender gap in sickness absence. We will use data from two large multi-centre RCTs in the Norwegian Sickness Absence Clinic (NSAC) on occupational health and return to work currently ongoing in Northern Norway. We will use registry data for these patients to evaluate background factors and follow up in terms of sickness absence, employment, long-term benefits, healthcare service utilisation covering a time span of 20 years. In WP1, we will explore six hypotheses for the higher sickness absence rates in women than men. These involve gender differences in: 1. specific health problems including symptoms and diagnoses, 2. thoughts about reasons for health problems and consequences for sickness absence, 3. beliefs about the curative or preventative effects of sickness absence, 4. experiences of work environment and work-home conflicts, 5. barriers for return to work once on sickness absence, 6. wishes, priorities, and expectations to career and other life priorities. Health problems commonly reported as reason for sickness absence are more common in women, and patients referred to the NSAC are more often women than men. In WP2, we will test if a clinical intervention to prevent sickness absence and promote return to work has merit to reduce the gender difference in sickness absence. We will systematically review the literature relevant for WP1 and 2 in the early phase of the project period.

Norwegian women have the highest sickness absence rate of all countries in the OECD, despite a good population health. The gender difference in sickness absence is relatively higher in Norway (70%) than in other OECD countries (50%), but the gender difference is observed in all economies where female labour force participation is high. This gender difference represents a major concern in terms of health, wellbeing, and gender equality and is largely unexplained in the research literature. No intervention has yet proven to be efficacious in reducing this gender gap in sickness absence. We will use data from two large multi-center RCTs on occupational health and return to work. To the best of our knowledge, these two RCTs constitute the largest within the field of work and health service delivery. The first RCT (n=1144) has successfully completed recruitment, and the second RCT (n=2500) will conclude recruitment during 2024. Patient data will be linked with high quality longitudinal register data from three different sources, containing data on employment, benefits, sickness absence and healthcare service utilisation covering a time span of 20 years. In WP1, we will go beyond the state-of-the-art and explore three existing hypotheses with a novel angle, in addition to two original hypotheses for the relatively higher sickness absence rates in women compared to men. WP1 is based on secondary analyses of uniquely rich data from the RCTs. This level of detailed data have previously not been available for research on the gender difference in sickness absence. In WP2, we will test the efficacy of a clinical intervention tailored to prevent sickness absence and promote return to work. Preliminary data indicates that there is high demand for this service in women, with a 70/30 split. This is as expected as the intervention targets those reporting symptoms of common mental disorders and/or musculoskeletal problems, conditions that are more prevalent in women than in men.