Introduction Despite more than half a century of research on occupational burnout (OB), little is known about its prevalence, etiology, treatment, or prevention. The lack of consensus on its definition and measurement has led to the use of various arbitrary definitions and measures of OB.

Objectives Within the Network on the Coordination and Harmonisation of European Occupational Cohorts (OMEGA-NET), we aimed at 1-assessing the state of the art on OB recognition in the 37 OMEGA-NET-participating countries, 2-elaborating a harmonized consensual definition of OB as a health outcome, 3-assessing the psychometric validity of the most used OB inventories, and 4-identifying the OB risk and protective factors.

Methods The first study was an on-line survey among occupational health specialists. The harmonized consensual definition resulted from the systematic review and semantic analysis of available OB definitions and a Delphi study. The two other studies were systematic reviews.

Results The survey showed that in 14 (38%) countries OB is acknowledged as an occupational disease. The results showed a high variability in OB diagnosis, in assessment of its work-relatedness, and in conditions allowing compensation of patients. The harmonized definition of OB was formulated in accordance with the Systematized Nomenclature of Medicine Clinical Terms and consensually approved by 50 experts from 29 countries. Among five most used tools for OB measurements, only two have a moderate evidence of their psychometric validity, the CBI and OLBI. Regarding the 261 OB predictors examined, we found a moderate evidence for the harmful effects of Job demands predictors n=6) and Negative job attitudes and for the protective effect of Adaptive coping (small effect sizes) and Leisure (small to medium effect sizes).

Conclusions These results will help harmonizing the future research, through the use of the harmonized definition and the most valid measurement tools, and facilitate decision-making and interventions regarding OB.