American Board of Orthodontics (ABO) Discrepancy Index and peer assessment rating (PAR) index with models versus photographs.

Background: The objectives of this study were to determine whether rating systems, such as the Peer Assessment Rating (PAR) and the American Board of Orthodontics Objective Grading System (ABO-OGS) can be applied to intraoral photographs.

Methods: Models and photographs of 50 cases were graded by 4 raters, and a 20% repeat of randomized cases was completed 2 weeks later. Intraclass correlation coefficients (ICCs) were used to assess inter- and intra-rater agreements, as well as the level of agreement between the ratings on models and photographs.