Objective: The aim of this study was to determine the frequency of oral health-related quality of life (OHRQoL) impairment and to establish norm values for the German version of the Child Perceptions Questionnaire (CPQ-G11-14, 35 questions) in the general population aged 11 to 14 years.
Subjects and methods: Data were collected in a national survey (n=1,597, mean age: 12.5 ± 1.2 years, 49.3% female) and subjects sampled using a multistage technique. OHRQoL was measured with the CPQ-G11-14, which was presented in a personal interview. Norm values were computed for the CPQ-G11-14 summary score (simple sum of all item responses). The CPQ-G11-14 summary score distribution was described by empirical cumulative distribution functions. Because orthodontic treatment was closely associated with CPQ-G11-14 summary scores, percentile-based norms were stratified by this variable.
Results: The CPQ-G11-14 mean was 12.6 ± 15.9 units. There was no influence of age (p>0.05) or gender (p>0.05) on the CPQ-G summary scores, but the summary scores varied according to orthodontic treatment status (p<0.001). Among the general population sample, CPQ-G11-14 scores of the 50% less-impaired subjects were ≤7. The same percentage of subjects undergoing orthodontic treatment had scores of ≤13 and those without orthodontic treatment had scores of ≤5. We observed scores of ≤32 points in 90% of the population. That figure was ≤50 points for subjects undergoing orthodontic treatment and ≤21 points for those without orthodontic treatment. The most frequent problems the children and adolescents reported (CPQ-G answers "often" and "very often") were "breathing through the mouth" (13.0%), "mouth sores" (4.4%) and "bad breath" (4.3%).
Conclusion: The norm values we present provide a frame of reference for future cross-sectional studies in the general population and in patient populations with specific oral conditions when measuring OHRQoL by CPQ-G11-14 in children and adolescents aged 11 to 14 years old.