Overtime work and well-being : opening up the black box

The aim of this thesis was to render more insight into the relationship between overtime work and well-being. The thesis contains four studies on this topic and the findings resulted in the following conclusions: (1) Overtime work should not be conceptualized as a phenomenon which, by definition, has negative implications for health and well-being. The thesis shows that overtime can be related to both positive and negative well-being. (2) Overtime work comes in many qualities and the quality of overtime work defines its relationship with well-being. That is, moderate overtime is related to reduced well-being in case of (a) adverse work characteristics (high job demands combined with low autonomy), (b) mandatory overtime work (especially when it is not rewarded), and (c) insufficient recovery opportunities. Conversely, overtime work is related to positive well-being in case of (a) favourable work characteristics (high autonomy), (b) voluntary overtime work, (c) high worktime control, and (d) sufficient recovery opportunities. (3) Overtime work and long work hours are non-identical concepts and should be treated as such in research. (4) The thesis also adds to the knowledge on overtime work as it provides insight into the prevalence of overtime work in the Netherlands. The studies revealed that overtime work is highly prevalent in the Netherlands (67% of fulltimers, 62% of substantial part-timers and 47% of marginal part-time works overtime) and Dutch employees work on average 3.5 overtime hours a week. About 30% of the overtime workers with a fulltime contract works overtime purely voluntary and 15% purely involuntary; 38% receives no rewards for overtime work. Based on the results of the studies, this thesis underlines the importance of favourable work characteristics not only during normal work hours but also during overtime hours. Job-redesign suggestions regarding optimalization of the quality of overtime work are formulated for employers.