Exploratory and confirmatory factorial analysis of the OHIP-Edent instrument

Several instruments have been used to measure oral health-related quality of life (OHRQoL). The Oral Health Impact Profile (OHIP) questionnaire was based on the concept that sequential events related to oral diseases can cause discomfort, functional limitations and consequently, result in dysfunctions and even disabilities. There are few studies in the literature that structurally analyze the instruments to verify whether they measure the requirements to which they were designed to. The objective of the study was to evaluate the internal structure of the OHIP-Edent questionnaire. The OHIP-Edent was administered to 54 edentulous patients' wearers of conventional complete dentures. For structural analysis, an exploratory factorial analysis (EFA) was carried out. After determining the internal consistency of the model (Cronbach's alpha = 0.88), the fit was checked using the root mean square error approach (value 0.04), the comparative fit index (value 0.982) and the Tucker-Lewis index (value 0.976). After analysis of the 19 questions and the seven domains proposed in the OHIP-Edent questionnaire, the hypothetical factorial model showed three dimensions denominated "Physical Impact", "Psychological Impact" and "Social Impact". In this sample of conventional complete denture wearers, the OHIP-Edent seems adequate to measure the "Physical Impact", "Psychological Impact", and "Social Impact" of the OHRQoL. The confirmatory factorial analysis confirmed the model and, through adjustment indexes, it was verified that the three dimensions have convergence and consistence adequate in order to characterize the OHRQoL construct with validity.