The public sector in general and the municipal health care sector in particular is challenged by high sick leave rates among home-care personnel [1–3]. The sector also reports problems in recruiting and holding on to new employees. Demographic changes marked by a growing size of the population of elderly citizens, expectably in demand of personal care and home care, adds further to this vicious circle . Several models have been developed in an attempt to capture positive and/or negative factors in the working environment explaining adverse effects among employees, i.e. sick leave, turn-over intentions and low engagement. Two models have gained general acceptance in the field of occupational health; effort-reward imbalance model , and the demand-control-(support) model . However, these two models may be too static, i.e. the items used do not offer adequate descriptions of important work environment characteristics in all occupational settings . A more recent model (the job demands-resources model)  proposes that every organisation has its own unique work environment characterised by demands and resources. It further claims that health may be affected by sustained high job demands and turnover intentions may be a consequence of sustained low job resources .
The National Research Centre for the Working Environment (NRCWE) conducted a national survey of the municipal eldercare in Denmark in 2004–2005 ; the survey reported a 34% higher level of sick leave among home-care personnel than among administrative employees within the eldercare sector . Numerous demands and resources in the psycho-social and physical working environment along with lifestyle factors were found to be associated with high self-reported sick leave levels . The survey also reported a significantly higher risk of having high (more than four weeks) and moderate (one to four weeks) levels of sick leave among young homecare employees (<40 years). This increased risk was partly explained by the experience of more role conflict, less commitment to the work place and less wellbeing .
It has been suggested that frequent short-term sick leave is associated with work environment factors, whereas long-term sick leave is associated mainly with ill health and reduced workability [12, 13]. However, few studies have analysed if psychosocial work factors are more strongly associated with frequent short-term sick leave than with long-term sick leave . In studies on health care workers, the total number of sick leave days per year was associated with high psychological demands, high physical workload  and low social support . The number of sick leave spells was found to be related to physical and psychological work demands [16–19]. Elstad et al. reported proportionality in the association between the number of perceived stressful work characteristics and the number of spells . Bullying is another factor that is associated with an increased risk of a new spell of sick leave . High levels of decision authority, perceived meaningfulness of work, commitment to the workplace, quality of leadership and a good team climate may protect against sick leave [17, 21, 22]. The effect of social support on spells of sick leave varies between studies [16, 19, 23].
Generally, younger age is related to a higher frequency of spells [17, 19, 20, 23, 24], and older age is associated with fewer, but longer spells [17, 18, 24]. Moreover, age seems to modify the associations between work factors and different sick leave measures .
Apart from the effect of age, inconsistencies in the reported associations between work factors and sick leave are considerable. This was suggested to be due partly to the different measures of sick leave themselves [12, 26]. Hence, most studies analyse length of sick leave and frequency of spells separately, and any independent association between length versus frequency and psychosocial work factors therefore remains unknown. However, in a study where nursing assistants were compared with doctors, the former had a higher risk of having incident sick leave spells of 1–3 days (adjusted for medium and long spells) and sick leave spells of 4–14 days (adjusted for short and long spells) than the latter .
The high levels of sick leave in the elderly care indicate that early detection of unfavourable changes in the working environment may be instrumental in maintaining the employees’ wellbeing, productivity and viability within the institution or company. According to the literature, an association between total sick leave length and a poor working environment may be more likely to be due to a frequent short-term sick leave pattern than a non-frequent long-term sick leave pattern [12–14], and even more so in young employees than in older colleagues . Long-term sick leave spells, on the other hand, seem to be more strongly associated with a poor general health than short spells. Whether these assumptions are valid within the elderly care sector has not yet been established.
This study draws on workplace-registered sick leave data to explore if sick leave patterns, i.e. the number of short-term sick leave spells or merely their duration, are associated with self-reported, unfavourable psychosocial work factors. If associations can be identified, the employers’ sick leave register may be a fruitful source for initiating preventive work environment measures.
This study aims to explore associations between sick leave patterns and psychosocial work factors in elderly care and thereby enhance the potential for using the employers’ sick leave register to launch interventions aimed at improving the working environment and, hence, the employees’ wellbeing, productivity and viability.