There is substantial variation in mental health-related sickness absence duration attributable to occupational health professionals, with median absence duration ranging from 18 weeks or less for high-performing OHPs to 28 weeks or more for low-performing OHPs.
Key Findings
Results
Substantial variation in mental health-related sickness absence duration is attributable to occupational health professionals (OHPs).
The study analyzed more than 30,000 sickness absence cases involving employees diagnosed with mental health-related disorders across multiple sectors.
A cross-classified multilevel model was applied to estimate variance attributable to OHPs while controlling for other sources of variation.
The results show substantial variation in mental health-related sickness absence duration between OHPs, denoted as a significant variance component in the model.
Results
High-performing OHPs are associated with a median absence duration of 18 weeks or less, while low-performing OHPs are associated with a median absence duration of 28 weeks or more.
This represents a difference of at least 10 weeks in median sickness absence duration between high- and low-performing OHPs.
These differences correspond to 'marked differences in return-to-work outcomes' as described by the authors.
The comparison between high- and low-performing OHPs illustrates the practical significance of OHP-level variance.
Results
Including OHP- and organization-level random effects reduced the estimated individual-level variance by approximately 50%.
This reduction indicates that differences across providers and employers are relevant factors in sickness absence duration.
The finding suggests that individual-level variance in absence duration is substantially explained by which OHP and organization an employee is associated with.
This result supports the argument that OHPs and organizations together contribute to differences in return-to-work outcomes.
Results
Individual, organizational, and sectoral factors each contribute considerably to differences in sickness absence duration.
The cross-classified multilevel model partitioned variance across individual, OHP, organizational, and sectoral levels.
The study covered employees across multiple sectors, allowing sectoral variation to be estimated.
The authors note that all these levels — not just OHP characteristics — are relevant sources of variation in absence duration.
Conclusions
OHPs and organizations are argued to need to work in concert to reduce sickness absence durations in mental health-related cases.
The authors argue this based on the finding that both OHP-level and organization-level variance are substantial contributors to absence duration.
Future research is called for to identify which specific OHP characteristics and practices are most helpful in reducing absence duration.
The study is described as providing a 'comprehensive quantitative analysis' that was previously lacking in the literature on OHP influence on return-to-work outcomes.
What This Means
This research suggests that the specific occupational health professional (OHP) — such as an occupational physician or case manager — assigned to a worker on sick leave due to mental health problems has a substantial impact on how long that worker stays off work. By analyzing over 30,000 sickness absence cases across multiple industries, the researchers found that employees managed by high-performing OHPs returned to work in a median of 18 weeks or less, while those managed by low-performing OHPs had a median absence of 28 weeks or more — a gap of at least 10 weeks. This variation was not explained simply by differences in the workers themselves, but was genuinely tied to which professional was handling their case.
The study also found that the organization an employee works for plays an important role, alongside individual and sector-level factors. When the researchers accounted for which OHP and which employer was involved, the unexplained variation at the individual worker level dropped by about 50%, suggesting that much of what looks like individual differences in recovery is actually driven by the professional and organizational context around the worker.
This research suggests that improving occupational health care systems — both by supporting OHPs to develop better practices and by encouraging organizations to create environments that facilitate return to work — could meaningfully reduce the length of mental health-related sick leave. The authors call for future studies to identify exactly which OHP behaviors and characteristics lead to better outcomes, as this study establishes that the variation exists but does not yet explain what drives it.
Timp S, van Foreest N, van Rhenen W. (2026). Variation in mental health-related sickness absence duration: The role of occupational health professionals.. PloS one. https://doi.org/10.1371/journal.pone.0348115