Comparison of Treatment Outcome Assessment for Class I Malocclusion Patients: Peer Assessment Rating versus American Board of Orthodontics-Objective Grading System

Abstract

Purpose: The purpose of this retrospective study is to investigate the degree of coincidence between the peer assessment rating (PAR) index and American Board of Orthodontics objective grading system (ABO-OGS) in the assessment of orthodontic treatment outcomes of Class I malocclusion cases. Materials and Methods: The sample consisted of 26 Class I patients. The PAR index was used for evaluation of pre-(T0) and posttreatment (T1) casts, and the ABO-OGS for assessment of T1 casts. If there was a reduction in PAR scores from T0 to T1 of more than 30%, the label `PAR+` was given to the case, and if not, it was labeled `PAR-`. If the ABO-OGS was less than 27, the label `OGS+` was given to the case and if not, it was labeled `OGS-`. `A PAR-only qualified group` (PAR+), `ABO-OGS-only qualified group` (OGS+), `both indices qualified group` (PAR+/OGS+), and `both indices disqualified group` (PAR-/OGS-) were compared with a Wilcoxon rank-sum test, sensitivity/specifi city test and Spearman`s correlation test. Result: PAR scores for T0, T1, and percentage reduction were 21.1, 6.4, and 65.9%, respectively, and 35.4 for ABOOGS. The distribution of the `PAR+/OGS+`, `PAR+`, and `PAR-/OGS-` group was 19.3%, 76.9%, and 3.8%, respectively. The T0-PAR, T1-PAR and PAR point reductions for the `PAR+` group were significantly higher than those of `PAR+/OGS+` groups (23.1 vs. 15.6; 6.7 vs. 4.6; and 16.5 vs. 11.0; all P