Introduction Mental health conditions are a major contributor to productivity loss and are common after injury. This study quantifies postinjury productivity loss and its association with preinjury and postinjury mental health, injury, demographic, health, social and other factors.

Methods Multicentre, longitudinal study recruiting hospitalised employed individuals aged 16–69 years with unintentional injuries, followed up at 1, 2, 4 and 12 months. Participants completed questionnaires on injury, demographic factors, health (including mental health), social factors, other factors and on-the-job productivity upon return to work (RTW). ORs were estimated for above median productivity loss using random effects logistic regression.

Results 217 adults had made an RTW at 2, 4 or 12 months after injury: 29% at 2 months, 66% at 4 months and 83% at 12 months. Productivity loss reduced over time: 3.3% of working time at 2 months, 1.7% at 4 months, 1% at 12 months. Significantly higher productivity loss was associated with preinjury psychiatric conditions (OR 21.40, 95% CI 3.50 to 130.78) and post-traumatic stress avoidance symptoms at 1 month (OR for 1-unit increase in score 1.15, 95% CI 1.07 to 1.22). Significantly lower productivity loss was associated with male gender (OR 0.32, 95% CI 0.14 to 0.74), upper and lower limb injuries (vs other body regions, OR 0.15, 95% CI 0.03 to 0.81) and sports injuries (vs home, OR 0.18, 95% CI 0.04 to 0.78). Preinjury psychiatric conditions and gender remained significant in analysis of multiply imputed data.

Conclusions Unintentional injury results in substantial productivity loss. Females, those with preinjury psychiatric conditions and those with post-traumatic stress avoidance symptoms experience greater productivity loss and may require additional support to enable successful RTW.