The German version of the Oral Health Impact Profile--translation and psychometric properties

The need for cross-culturally adapted oral-health specific health outcome measures is increasingly recognized in Germany. Following accepted cultural adaptation technique guidelines, we report the development of the German version of the Oral Health Impact Profile (OHIP). The original 49 items were translated using a forward-backward method. A de novo development of German items established content validity. A priori hypothesized associations between the OHIP summary score and self-reported oral health and five oral disorders were confirmed in a random sample of the general population (n = 163, age 20-60 yr). These associations were interpreted as support for construct validity. The instrument's responsiveness, as indicated by a mean OHIP summary score change from 45.0 to 28.3, was established in 67 consecutive patients treated for temporomandibular disorder pain (age 19-85 yr; 72% women). Test-retest reliability was demonstrated by intraclass correlation coefficients of 0.63-0.92 for dimensions and summary scores (convenience sample, n = 30, age 18-85 yr; 53% women). Internal consistency was high (Cronbach's alpha > 0.74). Sufficient discriminative and evaluative psychometric properties of the Oral Health Impact Profile German version (OHIP-G) make the instrument suitable for assessment of oral health-related quality of life in cross-sectional as well as longitudinal studies.