Psychometric properties of the Croatian version of the Orofacial Esthetic Scale and suggestions for modification.

PURPOSE The aims of this study were to develop a Croatian version of the Orofacial Esthetic Scale (OES) and to test its psychometric properties. MATERIALS AND METHODS The English version of the OES was translated into Croatian (forward-backward method). The original 11-point scale as well as a 5-point scale (1 = unsatisfactory, 5 = excellent) were used. Convergent validity was tested on 126 subjects, and discriminative validity was tested on the same subjects divided into four groups: esthetically normal patients (n = 25), esthetically impaired patients (n = 42), esthetically normal controls (n = 37), and esthetically impaired controls (n = 22). Test-retest reliability was tested on 43 subjects. Responsiveness was tested on 32 esthetically impaired patients who received prosthodontic treatment. RESULTS An additional explanation was added to the first two items of the OES. Convergent validity was confirmed by the association between OES scores and self-reported oral esthetics and three questions from the Oral Health Impact Profile related to esthetics (correlation coefficients ranged from 0.734 to 0.811, P < .001). Discriminative validity showed the results as predicted. Test-retest reliability showed high intraclass correlation (0.79 to 0.95) and no significant differences between the two administrations of the 5-point OES scale (P > .05). The 11-point OES scale showed significant differences for questions 3 and 8 (P < .01). Internal consistency showed high Cronbach alpha values (0.802 to 0.962). Responsiveness was confirmed by a significant difference between baseline and follow-up (P < .001) and a high effect size. CONCLUSION Psychometric properties of the Croatian version of the OES render the instrument suitable for the assessment of esthetics in Croatia. The authors recommend changing the first two items by adding the explanation that the questions are related to the lower third of the face and using the 5-point scale for rating.