Are there differences between officers and ratings on merchant vessels concerning effort-reward imbalance: a cross-sectional maritime field study.

Purpose: Today, measures to economise in the operation of ships can cause either an effort-reward imbalance or health impairments. The goal of this study was to assess the risk of effort-reward imbalance including overcommitment among officers and ratings on merchant vessels during their assignments and to evaluate lifestyle factors of seafarers as well as the health-promoting conditions on board.

Methods: A study sample of 308 male seafarers was examined during a total of 20 sea voyages on German container ships (participation rate 91.9%).

Results: Only 11 seafarers were identified as having an increased health risk of an effort-reward imbalance (ER ratio > 1). Officers tended to have a higher risk of an elevated ratio than ratings (4.4% vs. 3.1%) and also showed a significantly higher risk of an ER ratio above the median (58.8% vs. 41.8%; p = 0.022). Compared to land-based populations, the average overcommitment score of seafarers was high (17.9)-particularly among officers (20.3 vs. 16.5; p = 0.031). This corresponded to an elevated risk of overcommitment among officers compared to ratings (OR 2.14; 95% CI 1.78-2.37). This elevated risk remained significant after adjustment for age (OR 2.11; 95% CI 1.76-2.35) and job-related stressors.

Conclusion: Although an elevated risk of effort-reward imbalance was only observed in few seafarers, this study revealed a high prevalence of overcommitment particularly among officers. In the course of time, overcommitment can lead to mental exhaustion. Therefore, shipboard health-promoting conditions need to be optimised.