Adaptation and Validation of the Malay Version of the Index of Dental Anxiety and Fear (IDAF-4C(+)) for Malaysian Secondary School Children

BACKGROUND: Many questionnaires have been developed to measure dental anxiety and fear. Among them is the Index of Dental Anxiety and Fear Scale (IDAF-4C(+)), which consists of a dental anxiety and fear module (IDAF-4C), a phobia module (IDAF-P) and a stimulus module (IDAF-S). The objective of this research was to report the adaptation and validation of the IDAF-4C(+) for Malaysian secondary school children. METHODS: This was a cross-sectional validation study. The original English version of the IDAF-4C(+) was translated into Malay, back-translated, and then sent for content validation via an expert validation and face validation by the target student population. Three hundred and seventy questionnaires were then distributed among 16-year-old school children. Confirmatory factor analysis (CFA) was conducted for the IDAF-4C module using a bootstrapped maximum likelihood estimator. Spearman’s rank correlation was used to assess the relationship between the IDAF-S and IDAF-4C modules. Intraclass correlation (ICC) was used to determine the stability of the IDAF-S and IDAF-4C modules, while kappa values were used for the IDAF-P module. RESULTS: The response rate was 86.5% for CFA and 76.9% for stability. CFA showed the existence of only one factor with a reliability estimate of 0.921, obtained via Raykov’s procedure. All items in the IDAF-S module were significantly correlated with the IDAF-4C module (P < 0.001). The IDAF-S and IDAF-4C modules were stable, as determined via a two-way mixed model with absolute agreement, a single measure and a Case 3 ICC (A, 1). The IDAF-P module showed satisfactory stability, as assessed via kappa values. CONCLUSION: The Malay version of the IDAF-4C(+) is valid and reliable in measuring dental anxiety and fear among Malaysian secondary school children.