The Croatian version of the Oral Health Impact Profile Questionnaire.

Purpose of this study was to develop a Croatian version of the Oral Health Impact Profile questionnaire (OHIP--CRO49), following the accepted cross-cultural adaptation technique guidelines. The original version was translated by using a forward-backward translation method. The psychometric properties of the OHIP-CRO49 were tested. To test the construct validity 163 randomly selected subjects and 26 prosthodontic patients participated. The construct validity was supported by the association between the OHIP-CRO49 sum-scores and the self-reported oral health and five oral disorders. The test-retest reliability was tested on 30 prosthodontic patients and 30 students, and it was supported by high intraclass correlation coefficients (r = 0.63 to 0.95). To test the internal consistency 163 randomly selected subjects (general population), 26 prosthodontic patients and 29 dental students participated, and it was supported by high Cronbach's alpha coefficients (0.60 to 0.97). The resposiveness was tested on 21 patients with a treatment demand (toothache), and was supported by a statistically significant mean OHIP-CRO49 score difference (from 108.48 to 27.57) and a high effect size (2.96 and 3.48). Adequate psychometric properties in a typical patients' population make the new instrument suitable for assessment of Oral health-related quality of life (OHRQoL) in Croatia.