Estimating the reliability of the modified dental anxiety scale: A systematic review and reliability generalization meta-analysis

The reliability generalization meta-analysis of the Modified Dental Anxiety Scale (MDAS) synthesized a total of 128 α coefficients from 118 studies encompassing 95,588 participants. This synthesis was performed using three-level random-effects models with CR2 inference and Bonett transformation. The pooled internal consistency α = 0.882 (95% CI (0.873, 0.889)) and 95% PI (0.759, 0.942). The language moderator showed a strong effect that persisted after continent adjustment. Furthermore, while mean age and sample size were found to be reliably associated with α, other moderators were found to be invalid. PET/PEESE and Egger tests indicated minimal small-study effects, and reliability induction was prevalent (76.1%). Overall, MDAS scores show high reliability; however, they are also sensitive to contextual effects. It is important for studies in this field to report sample-specific alpha values along with CIs using omega/ordinal alpha. Practical benefits of using MDAS are presented for dental health professionals and researchers.