Psychometrics Properties of the Items of Parenting Style Inventory according to Item-Response Theory

The main condition for using questionnaires is their validity and reliability. In the present study, the psychometrics properties of questions of parenting style inventory have been examined according to item-response theory, among 576 mothers of elementary school students in Tehran. The sample was selected by means of Multi-stage cluster sampling method. This study, due to the nature of its subject and objectives, is a descriptive research based on psychometric methods. In fitting the IRT-model–based approach with the inventory items and estimating the level of difficulty and the coefficient of determination of items separated based on subscales, the ltm and eRm packages were employed in software R. Results showed that the graded response model is a better fit in comparison with partial credit model, with the questions of parenting style inventory. The results of the estimation of the items parameters and items characteristic curves showed the items 17, 21, 24 of the permissiveness parenting style, items 4, 11 of authoritative parenting style and items 12, 18 of the authoritarian parenting style have a low desirability.