Exploring the Interaction between Physical, Psychosocial, and Neck Pain Symptoms in Construction Workers.

Objective: Construction workers are significantly vulnerable to musculoskeletal disorders, yet the number of studies conducted in developing nations-where these workers significantly contribute to the economy-remains insufficient. This study aims at exploring the interaction between physical and psychosocial exposure to the onset of neck pain or symptoms amongst construction workers in a developing country.

Methods: Using a cross-sectional study design, a total of 235 respondents from various construction projects participated in this study. Participants were assigned into one of four exposure groups: low physical and low psychosocial (which served as the reference group); low physical and high psychosocial; high physical and low psychosocial, and high physical and high psychosocial. To quantitatively assess the interaction, we calculated the relative excess risk due to interaction (RERI), attributable proportion (AP), and synergy index (SI).

Results: Workers experiencing high levels of both physical and psychosocial risk factors had the highest odds ratio (OR) of neck symptoms (OR: 12.63, 95% confidence interval (CI): 3.39 - 46.99) compared to other groups. The AP (AP: 0.33, 95% CI: -0.24 - 0.90), RERI (RERI: 0.40, 95% CI: -0.99 - 1.79), and SI (SI: 1.69, 95% CI: -1.77 - 5.15) revealed an interaction between physical and psychosocial factors that increases the OR of neck symptoms.

Conclusions: This result suggests that physical risk factors at work become significantly more detrimental when paired with high psychosocial stress. Hence, ergonomic interventions in the construction industry aiming to reduce musculoskeletal disorders should consider both physical and psychosocial risk factors concurrently.