Translation and psychometric properties of the Swedish version of the Index of Dental Anxiety and Fear (IDAF-4C⁺)

Dental anxiety (DA) is a common condition, with significant medical, psychological, and social consequences. High-quality psychometric tools for the assessment of dental anxiety are necessary for clinical and research purposes. The aim of this study was to adapt the Index of Dental Anxiety and Fear (IDAF-4C⁺) to the Swedish language and to explore the psychometric properties of the translated version. The study included a clinical sample (n = 414; 17-91 yr of age) and a non-clinical sample (n = 51; 19-47 yr of age). The scales used were the IDAF-4C⁺, the Single-Question Assessment of Dental Anxiety (SQDA), the Dental Fear Survey (DFS), and the Internal Health Locus of Control (IHLOC). The Swedish IDAF anxiety module showed a clear, one-dimensional structure, good internal consistency (Cronbach's alpha = 0.95), and adequate validity, as evidenced by strong correlations with the other DA measures (SQDA and DFS) and weak correlations with the IHLOC. In addition, the IDAF phobia module and the IDAF stimulus module were strongly correlated with the other DA measures. To conclude, the study shows promising findings for the reliability and validity of the Swedish translation of the IDAF-4C⁺, as a useful measure of dental anxiety in research and clinical practice.