Objectives Long-term sickness absence is a risk factor for leaving the workforce, causing economic stress and deteriorating health. Women have higher rates of sickness absence compared to men in most, but not all, European countries. Reasons for apparent gender differences are currently poorly understood, but hypotheses include that women may have more health problems (particularly those associated with reproductive health). Other hypotheses for gender differences include gendered health beliefs, attitudes/norms to sickness absence, work factors, work–family conflict, or barriers to return-to-work. This umbrella review aimed to synthesize and critically appraise the empirical evidence underpinning these hypotheses.

Methods Following PRISMA and Joanna Briggs Institute methodological guidelines, a systematic search of seven electronic databases was conducted for peer-reviewed reviews (eg, systematic reviews, scoping reviews, critical reviews) and meta-analyses reporting on gender and sickness absence. The review protocol was pre-registered on PROSPERO.

Results In total, 133 reviews were eligible for inclusion, of which 12 directly focused on gender differences in sickness absence. Only three hypotheses were investigated frequently and, although there was strong face validity, there was limited and mixed-quality underpinning empirical evidence. There was a surprising lack of focus on men and sickness absence.

Conclusion Despite much research, the underlying causes for a gender gap in sickness absence remain poorly understood. Our findings highlight the need for caution when interpreting proposed hypotheses as established explanatory evidence. Whatever the cause, any gender difference in sickness absence is a gender equality problem, regardless of the cause. Future research should aim beyond describing gender differences to critically evaluating risk factors to develop prevention strategies.

Key terms absenteeism; gender; gender difference; meta analysis; meta review; review; sick leave; sickness absence; systematic review; woman; workplace

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