Validating the parental reflective functioning questionnaire - infant version using a rasch model.

Parental reflective functioning is the parent's ability to reflect on the psychological processes in their child and in themselves as a parent. Recently, an infant version of the Parental Reflective Functioning Questionnaire, PRFQ-I, has been developed and validated using confirmatory factor analyses. The present study aims to validate the PRFQ-I using a Rasch model in a sample of 531 Danish mothers at risk of depression and their infants aged 2-11 months. Our findings indicate that seven response categories were too many for the mothers to distinguish across all items. Prementalizing showed adequate psychometric properties, while Certainty of Mental States and Interest and Curiosity required recoding with 4 and 5 as the optimal scores, respectively. After rescoring, both subscales overall showed adequate psychometric properties. However, shortening Certainty of Mental States may be advisable due to local dependency between items 8 and 17. Additionally, items 2 and 14 ("I always know what my child wants" and "I always know why I do what I do to my child") may function better as a separate subscale. We recommend that scores on both Certainty of Mental States and Interest and Curiosity should be analyzed and interpreted in a curvilinear rather than linear manner.