Predictors of occupational burnout in Swiss bus drivers: results from the TRAPHEAC study

Abstract Background Occupational burnout is a growing public health concern with severe consequences for individual health and organizational performance. Despite multiple stressors inherent to public transport work, research on bus driver burnout remains scarce. This study aimed to estimate burnout risk among Swiss bus drivers and explore specific occupational predictors to inform targeted prevention strategies. Methods We conducted a cross-sectional analysis within the Swiss Transport Personnel Health Cohort (TRAPHEAC), including 424 bus drivers who completed all baseline questionnaires (June–October 2024). Burnout was assessed using the 12-item Burnout Assessment Tool (BAT-12), and work stress was measured via the Effort–Reward Imbalance (ERI) model. Fifteen working conditions were evaluated as potential predictors. Statistical analyses included multilevel linear regression models with transport company as a random intercept, controlling for age, sex, and interaction terms. Stratified analyses by sex and career duration were performed. Model performance was assessed using Akaike Information Criterion (AIC) and marginal R². Results Among participants (mean age 49.5 years; 16.1% women), 17.2% were at risk and 15.3% at high risk of burnout. The mean ERI score was 1.25 (SD = 0.58), indicating greater effort than reward. ERI showed a significant dose–response association with burnout (β = 0.37; 95% CI: 0.31–0.42), with a stronger association in men (β = 0.47) than in women (β = 0.31). Stratification by career duration (≤ 3 years versus > 3 years) suggested higher vulnerability among less experienced drivers. In multivariable models, daily fear of accident (β = 0.63), internal organizational hostility (β = 0.30), frequent aggression from passengers, urban driving, and number of > 10-hour workdays per week (β = 0.08 per day) were significant predictors. Protective factors included amenities in break areas. Conclusions Swiss bus drivers face substantial psychosocial stress, with burnout risk strongly linked to effort–reward imbalance and several specific working conditions. Interventions should prioritize reducing long workdays, mitigating aggression, improving organizational climate, and enhancing break facilities. Regulatory measures to limit excessive hours and promote safer, more respectful work environments are urgently needed to safeguard drivers’ mental health and ensure sustainable public transport services.