Figure 2.

Chronology of original definitions of occupational burnout. For each referenced original definition, the year of the first and updated publication, the first author’s name, main features, and the country of publication are reported along with the number of the corresponding secondary definitions, the frequency [N(%)]* and the timespan of their citations as quantified in the frame of the systematic review of 248 longitudinal studies on occupational burnout. The two definitions identified after the end of the systematic literature search (August 2018) were added and shown framed in dotted lines. *A single article can cite more than one definition.