Recorded Occupational Injury and Disease Episode Rates by Sex and Sector in a Spanish Mutual Collaborator, 2022–2025

BACKGROUND: Administrative comparisons of work-related disorders by sex can mislead without covered-population and work-distribution data. We estimated recorded occupational injury and disease episode rates from a Spanish mutual collaborator with the Social Security system and examined how contrasts changed after standardization for available employment characteristics. METHODS: This retrospective registry-based study included 312,596 episodes of occupational injury or disease recorded during 2022-2025 among affiliates (covered workers) aged 16-75 years with sex reported as men or women. Annual affiliate counts were used to calculate episodes per 1000 annual affiliates, women-to-men rate ratios and rate differences. Rates were directly standardized by year and broad sector; employment type was added in sensitivity analysis. Commuting and travel during the working day were analyzed separately. RESULTS: The pooled all-episode injury/disease rate was 38.36 per 1000 annual affiliates among women and 61.20 among men (rate ratio 0.627, 95% confidence interval 0.622-0.631). After standardization by year and sector, the rates were 38.28 and 55.69, respectively (rate ratio 0.687, 0.682-0.693). The overall traffic-coded rate was lower among women (rate ratio 0.915, 0.895-0.934), whereas the rate of all commuting episodes was higher (rate ratio 1.533, 1.502-1.565); travel during the working day was lower (rate ratio 0.675, 0.657-0.694). CONCLUSIONS: Denominator-based rates changed the interpretation of several occupational disorder proportions. Broad sector composition accounted for part, but not all, of the sex contrast. Occupational surveillance should link episode numerators to covered-population denominators and distinguish commuting from travel during work.