Training protocol and calibration of the International Caries Detection and Assessment System in a school-based clinical trial of elementary school-age children.

Objectives: This paper demonstrates International Caries Detection and Assessment System (ICDAS) training procedures and inter/intra-examiner reliability for lesion severity, activity, and filling criteria in an elementary school setting.

Methods: ICDAS training was conducted in December 2021 prior to a school-based cluster-randomized controlled trial. A total of 59 children (6-8 years old) in grades 1-2 from one school in Houston, Texas were recruited. Two licensed dentists received a 5-day training from an ICDAS trainer at the participating school. Thirty-eight children were evaluated at least once by each dental trainee, and 18 had repeat examinations. The ICDAS criteria were used to classify dental caries lesion severity (0-6), lesion activity (active/inactive), and filling material (0-9) of all visually available primary and permanent tooth surfaces. Inter and intra-examiner reliability between each dental trainee and the "gold standard" trainer was evaluated using Kappa statistics.

Results: For lesion severity, the examination indicated an inter-rater weighted Kappa of 0.77 (95% CI 0.71-0.82) and 0.82 (95% CI 0.77-0.87) for each trainee examiner compared to the gold standard examiner. The Kappas increased slightly from the first to second examinations (lesion-weighted Kappa: 0.76 to 0.84 and 0.82 to 0.84). The intra-rater reliability indicated excellent reliability for lesion and filling (0.83 to 0.94) and moderate for activity (0.58).

Conclusions: ICDAS training/calibration were essential to ensure accuracy and reliability of dental caries measurements. The study demonstrated that ICDAS training of dentists with no prior criteria experience is feasible in a community setting and can lead to high reliability and repeatability.