The reliability and validity of the restoration difficulty evaluation system tool for assessing the restoration of endodontically treated teeth: A pilot study.

Introduction: Restoration of endodontically treated teeth (ETT) is crucial for their long-term functionality, yet current practices lack structured approaches, leading to variable outcomes. The restorative difficulty evaluation system (RDES) offers a systematic method to assess restoration complexity tailored to each patient. This pilot study aims to evaluate RDES's reliability and validity in guiding clinicians' decisions on ETT restoration.

Methodology: Ten participants were recruited, and two endodontists independently assessed clinical parameters using RDES. Interrater reliability was assessed to determine agreement between examiners. Test-retest reliability was evaluated over two time points (baseline and 2 weeks). Face and content validity were assessed by a panel of 10 experts.

Results: Intrarater reliability was robust (Evaluator 1: r = 0.667 and Evaluator 2: r = 0.655). Interrater reliability was substantial (κ =0.783). Face validity affirmed RDES parameters' relevance with scores exceeding the impact score threshold. Content validity showed high item-rated content validity index (I-CVI) scores for both relevance (I-CVI [R]) and clarity (I-CVI [C]), resulting in high scale-level CVI scores, affirming all RDES items' appropriateness. The Gunning Fog Index (14.79) suggests tool's suitability for college junior or undergraduate-level readers.

Conclusion: The study demonstrates RDES's reliability and validity in assessing restoration complexity in ETT. Its systematic approach can inform treatment decisions, potentially enhancing patient outcomes.