[Consistency of the subjective evaluation of malocclusion severity by the Chinese orthodontic experts].

Objective: To assess the consistency of the subjective evaluation of malocclusion severity by the Chinese orthodontic experts.

Methods: Sixty-nine Chinese orthodontic experts subjectively evaluated the malocclusion severity for 120 cases which were selected randomly from 6 University orthodontic clinics by checking each case's pretreatment records including study cast, lateral head film, panoramic radiograph, facial photographs and patient chart. Each orthodontist was asked to independently rate the severity of every case into five grades: mild, mildly moderate, moderate, severely moderate and severe. Rating data was finally gathered to evaluate the intra-judge's reliability and the inter-judges' consistency.

Results: Weighted Kappa test revealed that 8.33% orthodontists showed excellent intra-judge's reliability (Kappa ≥ 0.81), 78.33% orthodontists showed good intra-judge's reliability (Kappa ≥ 0.61) and 96.67% specialists displayed general intra-judge's reliability (Kappa ≥ 0.41). And intra-class correlation coefficient demonstrated a high level of inter-judges' consistency (r=0.989, P<0.01).

Conclusion: Good intra-judge's reliability and inter-judges' consistency can be demonstrated in the subjective evaluation of malocclusion severity by the Chinese orthodontic experts, which could the basis for establishing the objective grading system of malocclusion severity.