Purpose Sickness absence has been identifed as needing to be addressed through multilevel interventions, but knowledge regarding optimal design and implementation of such interventions is scarce. The aim of this study was to evaluate the implementation and efects of a large-scale multilevel intervention in the public sector in Sweden.
Methods The overall efect of the intervention was assessed using mixed-efect models. Sickness absence data (before, and 6 or 12 months after the intervention) for 90 intervention groups and 378 reference groups was retrieved from administrative personnel systems from the two participating regional councils. The implementation processes were evaluated using qualitative content analysis of qualitative interviews conducted at two timepoints.
Results The results show that the vast majority of implemented measures were on an individual level and the integration of the intervention difered between the two regions. The reception and perception of the intervention activities seem to have been infuenced by the implementation process, and how well the interventions were communicated and integrated, both regarding the integration of the diferent interventions and their integration into the discrete context and existing routines. No short-term overall efects on sickness absence were found.
Conclusions The results point to the many challenges in implementing complex interventions, especially where organizational measures are involved—including adequate participation by, and communication between, the involved actors, as well as sufcient resources. The results indicate potential learning efects regarding the awareness of organizational factors in sick leave, after implementing and integrating multilevel strategies.