Validation of the translated and cross-culturally adapted Malocclusion Impact Questionnaire in young people seeking orthodontic treatment in Serbia

Abstract

Introduction/Objective. This study aimed to translate the original disease-specific Malocclusion Impact Questionnaire (MIQ) into Serbian and validate the new version in the cohort of young Serbian orthodontic patients. Methods. At the university clinic, 154 patients filled out the MIQ in Serbian before the start of the orthodontic treatment; 112 participants filled out the same questionnaire four weeks later. The Index of Orthodontic Treatment Need ? Dental Health Component (IOTN-DHC) and Peer Assessment Rating (PAR) pretreatment scores were recorded. Descriptive statistic, Cronbach?s ?, Spearman?s ?, and exploratory factor analysis, followed by parallel analysis for factor reduction, were calculated and analyzed. Results. One hundred forty-eight patients with no missing responses (51 male, 97 female), of the average age of 13.3 ? 2 years, had MIQ total scores mean of 10.14 ? 7.451. Internal reliability (? = 0.913), external reliability (? = 0.906; p = 0.000), construct validity tested by MIQ total scores and two global question scores? correlations (? = 0.682; p = 0.000 and ? = 0.366; p = 0.000), as well as clinical validity tested by correlations of MIQ total scores with PAR pretreatment scores (? = 0.181; p < 0.05), and IOTN-DHC scores (? = 0.192; p < 0.05) were positive and statistically significant. One item factor was extracted and it explained a large part of the cumulative variance. Conclusion. Reliability and validity of the translated and cross-culturally adapted MIQ in Serbian is satisfactory. It could be used for malocclusion-related quality of life assessments in young Serbian orthodontic patients.