Psychometric Properties of The Turkish Version of The Knowledge of Infant Development Inventory

Objective: This study aimed to adapt the Knowledge of Infant Development Inventory (KIDI) into Turkish and to evaluate its validity and reliability among parents of children aged 0–2 years. Methods: A methodological design was employed with 464 parents. The KIDI was translated into Turkish and The Content Validity Index and Content Validity Ratio were used to get opinions from the experts. The KIDI was analyzed using two scoring approaches. In the first, responses were categorized as accurate, attempted, underestimated, or overestimated, following original format. In the second approach, items were scored dichotomously as correct (1) or incorrect (0). Validity was assessed through exploratory factor analysis (EFA), concurrent validity using Spearman correlation with the CKCDI, and construct validity via tetrachoric EFA and Rasch modeling. Reliability was evaluated with Cronbach’s alpha (both classical and tetrachoric), test-retest, and item discrimination analysis. Results: Content validity was confirmed (CVI = 1.00), and EFA supported a four-factor structure consistent with the original scale, explaining 57.94% of the variance. The scale showed strong concurrent validity with CKCDI (r = .908, P < .001). In the dichotomous analysis, tetrachoric EFA and Rasch modeling indicated acceptable structural validity and item fit (infit/outfit range: 0.7–1.3). Cronbach’s alpha was 0.81 (tetrachoric), and the 27% upper-lower group comparison revealed strong item discrimination. Conclusion: The Turkish version of the KIDI was found to be a valid and reliable instrument for parent. Professionals can use this scale to assess parents’ understanding of infant developmental milestones and norms.