Psychometric properties of Croatian and Slovenian short form of oral health impact profile questionnaires.

AIM To develop Croatian and Slovenian versions of the 14-item Oral Health Impact Profile (OHIP) Questionnaire. METHODS The English original version of the OHIP questionnaire was translated into Croatian (OHIP-CRO14) and Slovenian (OHIP-SVN14) language by a forward-backward translation method. The psychometric properties of the OHIP-CRO14 and OHIP-SVN14 were tested. Concurrent validity was tested on 623 subjects (193 Croatian and 430 Slovenian), test-retest reliability on 115 subjects (55 Croatian and 60 Slovenian), internal consistency on 678 subjects (218 Croatian and 460 Slovenian), and responsiveness on 51 patients (21 Croatian and 30 Slovenian) in demand of treatment (toothache). RESULTS Concurrent validity was confirmed by the association between the OHIP summary scores and self-reported oral health (correlation coefficients ranged from 0.40 to 0.60, P<0.001). Test-retest reliability showed high intraclass correlation (correlation coefficients, 0.79-0.94). Internal consistency showed high Cronbach alpha (0.77-0.91). Responsiveness was confirmed by a significant difference between the mean OHIP score at baseline and follow-up (P<0.001 for both Croatian and Slovenian patients) and high effect size in Croatian and Slovenian patients in demand of treatment (3.00 and 0.57, respectively). CONCLUSION Psychometric properties of OHIP-CRO14 and OHIP-SVN14 render these instruments suitable for the assessment of Oral Health Related Quality of Life in Croatia and Slovenia.