Background and objectives: Musculoskeletal disorders (MSDs) account for more than 60% of compensated occupational diseases in Korea. Despite this burden, benchmarks of standardized ergonomic exposure and evidence on the combined effects of risk factors remain limited. This study aimed to construct a body part–specific ergonomic job-exposure matrix (JEM) and evaluate the independent and interactive effects of ergo-nomic, demographic, and work-related factors. Materials and Methods: We analyzed the data of 210,500 workers from the 2nd–6th Korean Working Conditions Survey (2009–2020). A JEM for arms/neck, back, and legs was developed and validated (κ≥0.79). Logistic regression models estimated adjusted odds ratios (aORs), and additive interactions were assessed using relative excess risk due to interaction (RERI), attributable proportion (AP), and the synergy index (SI). Results: High ergonomic exposure was strongly associated with MSDs across all body regions (aORs 2.3–2.5). Age 45 years, long working hours (52 h), and high job strain also increased risks (aORs 1.4–2.3). On the additive scale, ergo-nomic risk combined with older age showed consistent synergy (RERI up to 1.5; SI 1.5), whereas combinations with long working hours or job strain showed attenuation (RERI 0; SI 1). Women reported higher crude prevalence but lower adjusted odds (aOR ≈0.9). Conclusions: This nationally representative study demonstrates that ergonomic risk, age, long working hours, and job strain are major determinants of MSDs. The validated Korean JEM provides a standardized tool for surveillance and compensation. However, the cross-sectional design limits causal inference. Future longitudinal research with objective exposure measures is needed to strengthen causal inference and guide tailored preven-tion.
Lee et al. (Fri,) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: