Development and validation of a prediction model for long-term sickness absence based on occupational health survey variables.
OBJECTIVE
The purpose of this study is to develop and validate a prediction model for identifying employees at increased risk of long-term sickness absence (LTSA), by using variables commonly measured in occupational health surveys.


METHODS
Based on the literature, 15 predictor variables were retrieved from the DAnish National working Environment Survey (DANES) and included in a model predicting incident LTSA (≥4 consecutive weeks) during 1-year follow-up in a sample of 4000 DANES participants. The 15-predictor model was reduced by backward stepwise statistical techniques and then validated in a sample of 2524 DANES participants, not included in the development sample. Identification of employees at increased LTSA risk was investigated by receiver operating characteristic (ROC) analysis; the area-under-the-ROC-curve (AUC) reflected discrimination between employees with and without LTSA during follow-up.


RESULTS
The 15-predictor model was reduced to a 9-predictor model including age, gender, education, self-rated health, mental health, prior LTSA, work ability, emotional job demands, and recognition by the management. Discrimination by the 9-predictor model was significant (AUC = 0.68; 95% CI 0.61-0.76), but not practically useful.


CONCLUSIONS
A prediction model based on occupational health survey variables identified employees with an increased LTSA risk, but should be further developed into a practically useful tool to predict the risk of LTSA in the general working population. Implications for rehabilitation Long-term sickness absence risk predictions would enable healthcare providers to refer high-risk employees to rehabilitation programs aimed at preventing or reducing work disability. A prediction model based on health survey variables discriminates between employees at high and low risk of long-term sickness absence, but discrimination was not practically useful. Health survey variables provide insufficient information to determine long-term sickness absence risk profiles. There is a need for new variables, based on the knowledge and experience of rehabilitation professionals, to improve long-term sickness absence risk profiles.
a Department of Health Sciences, Community and Occupational Medicine , University Medical Center Groningen, University of Groningen, Groningen , Groningen , The Netherlands.|b Department of Epidemiology and Biostatistics , VU University Medical Center, VU University , Amsterdam , The Netherlands.
Corné
C
Roelen
c National Research Center for the Working Environment , Copenhagen , Demark.
Sannie
S
Thorsen
b Department of Epidemiology and Biostatistics , VU University Medical Center, VU University , Amsterdam , The Netherlands.
Martijn
M
Heymans
b Department of Epidemiology and Biostatistics , VU University Medical Center, VU University , Amsterdam , The Netherlands.
Jos
J
Twisk
a Department of Health Sciences, Community and Occupational Medicine , University Medical Center Groningen, University of Groningen, Groningen , Groningen , The Netherlands.|c National Research Center for the Working Environment , Copenhagen , Demark.
Ute
U
Bültmann
c National Research Center for the Working Environment , Copenhagen , Demark.|d Department of Public Health , University of Copenhagen , Copenhagen , Denmark.
Jakob
J
Bjørner
D000328:Adult; D005260:Female; D006306:Health Surveys / Q000379:methods*; D006801:Humans; D008297:Male; D008603:Mental Health; D008875:Middle Aged; D015233:Models, Statistical; D009426:Netherlands; D016272:Occupational Health / Q000592:standards / Q000706:statistics & numerical data; D011314:Preventive Health Services / Q000379:methods / Q000458:organization & administration; D011379:Prognosis; D012372:ROC Curve; D018570:Risk Assessment / Q000379:methods*; D018582:Sick Leave / Q000706:statistics & numerical data*; D017132:Workplace / Q000458:organization & administration
Clinical prediction models; general working population; risk assessment; sick leave; work disability prevention