Musculoskeletal pain, functional impact, and associations with recorded sex in an adult sample from Mashhad, Iran: a cross-sectional secondary analysis

We conducted a cross-sectional secondary analysis of musculoskeletal data collected within a parent survey in Mashhad, Iran, between May 2024 and March 2025. Descriptive analyses included all 1,074 participants with musculoskeletal data; recorded-sex comparisons included 1,049 participants (624 men and 425 women), and age-adjusted models included 1,037. A study-specific Persian questionnaire recorded pain in nine anatomical regions during the previous 12 months and 7 days, difficulty with normal activities, and physician consultation. In a post hoc exploratory analysis, multisite pain (at least two regions) affected 78.8% over 12 months and 62.3% over 7 days. Twelve-month knee and lower-back pain were reported by 65.5% and 57.8%, respectively. In exploratory age-adjusted analyses, women had lower prevalence than men of knee pain (prevalence ratio 0.71, 95% confidence interval 0.64–0.78; marginal prevalence difference −22.1 percentage points, −28.2 to −16.1) and lower-back pain (0.69, 0.61–0.78; −20.1 percentage points, −26.4 to −13.8). The direction of all 36 regional associations persisted after adjustment for available covariates. Estimates were unweighted and not adjusted for the intended sampling design. These findings describe the analyzed subset; selective participation, residual confounding, and sparse representation of younger and oldest adults restrict generalizability.