Effort-reward imbalance, "locked in" at work, and long-term sick leave.

Objectives: The objective was to study the relationship between a situation characterized as being in a "locked-in" position (LIP) in occupation and/or place of work, Effort-reward imbalance (ERI), and long-term sick leave.

Methods: The study population derived from one section of a cross-sectional study SKA (sick-leave, culture and attitudes), and comprised all employees at the Swedish Social Insurance Agency responsible for management and compensation of illness in the working population. The analyses were performed for 2,951 women and 534 men who had complete data. Logistic regression was used to calculate odds ratio (OR) for ERI and sick-leave, the latter only for women.

Results: The results showed a strong association between LIP within the place of work and ERI (for women OR = 3.28 95% CI 2.65-4.07, and for men 2.74 1.75-4.30). Also LIP within occupation resulted in high ERI (for women OR = 1.96 1.57-2.41, and for men 1.92 1.22-3.03). In women, ERI (OR = 1.40 1.15-1.70) as well as LIP within place of work (1.88 1.50-2.36) and within occupation (1.48 1.12-1.86) were associated with sick leave. ERI showed a significant mediating effect between LIP and sick leave, within place of work and within occupation (Z value 2.20 and 2.88, respectively).

Conclusions: High ERI is associated with a situation characterized by being locked-in within an occupation or/and within a place of work. The results thereby support the theoretical model of Effort-reward imbalance. The results show that high ERI and being locked in are associated with long-term sick leave. ERI is a potential mediator of the association between being locked in and sick leave.