Multidimensional item response theory to assess psychometric properties of GHQ-12 in parents of school children

Introduction: The multidimensional item response theory (MIRT) model provides an ideal foundation for assessing the psychological properties of a questionnaire designed with structure. This study aimed to present first use MIRT models investigate psychometric general health (GHQ-12) in parents school-aged children.
 Methods: A total 1104 school children-aged completed Persian version GHQ-12 questionnaire. One-dimensional IRT and two three factors were used observed scores each items as function subject's latent characteristics consider correlation between dimensions Goodness fit indices reported models, fits assessed best model. Individual described detail through characteristic curves, amount information carried by different was presented using curves.
 Results: analysis corresponding anxiety depression, social dysfunction loss confidence provided account data. showed that all fitted adequately. Items varied their discrimination ranged from 0.94 2.13, 1.31 2.74, 2.87 3.57 dysfunction, confidence, respectively. Moreover, 8 2 least depression dimensions, dimension most among GHQ-12.
 Conclusion: developed framework evaluating can be suitable alternative traditional approaches well unidimensional which has been restricted due structure