Oldenburg Burnout Inventory-IRT analysis
The Oldenburg Burnout Inventory (OLBI) assesses two subscales from measuring work-related syndromes of exhaustion and disengagement. In the present study, an item response theory approach was used to analyze all items of the measure. The participants were employees, occupied in various organizations in Greece (N = 617). Partial credit and generalized partial credit models were estimated for each subscale and a bifactor model was applied to the OLBI. The results revealed dimensionality issues for both subscales. Item discrimination and category threshold parameters revealed variations across certain items. According to the bifactor model, there is evidence for multidimensionality in OLBI, but the general factor is strong. Thus the OLBI can be treated as essentially unidimensional, although both subscales may be of additional value.