Staffing of Occupational Physicians and Occupational Health Nurses, and Coordinating Structure in Relation to the Health and Productivity Management Implementation Score: A Company Panel Study in Japan

Objective: To examine within-company associations of occupational health professional staffing and coordinating structure for Health and Productivity Management (HPM) promotion with the HPM implementation score. Methods: We analyzed an unbalanced panel of 3,966 companies (9,440 company-year observations) for fiscal years 2021–2023. The outcome was a relative HPM implementation score standardized among responding companies. Company fixed-effects models included staffing [ln(n + 1)], coordinating structure, fiscal-year fixed effects, ln-transformed employee count, and company-clustered robust standard errors. Results: Occupational health professional staffing was positively associated with the HPM implementation score (coefficient, 1.028, 95% CI 0.540–1.515, P<0.001). Other coordinating-structure categories had lower scores than an independent dedicated department (coefficients, −0.813 to −5.314; 95% CIs, −1.418 to −0.208 and −6.884 to −3.745; all P ≤ 0.008). Conclusions: Both factors were associated with HPM implementation within companies over time.