Mixed-methods Validation of the Brazilian OHIP-Edent Version Among Denture Wearers

Objectives:
To analyze the psychometric properties of the Brazilian version of OHIP-Edent instrument and to explore complete denture wearers’ interpretations of the impact of oral health on quality of life.
Methods: This is a convergent parallel mixed-methods study design. Twenty elderly participants, mean age 68.1±7.3 years old, seeking complete denture treatment answered the OHIP-Edent questionnaire before and after the delivery of new dentures. Participants were also interviewed via open-ended semi-structured questions; interviews were audio-recorded, transcribed and translated to English. Content analysis was performed based on Strauss and Corbin recommendations. Quantitative data were evaluated using exploratory factor analysis with polychoric correlation matrix. Additionally, Kaiser-Guttman criteria (eigenvalues>1) were used for factor retention. In order to interpret retention factors and determine internal reliability of the factorial model, Promax oblique rotation and Cronbach’s alpha coefficient test were performed. Qualitative and quantitative findings were integrated and compared.
Results: Factorial analysis and qualitative analysis confirmed that only two dimensions of the OHIP-Edent best fit the model, functional and psychosocial, instead of the seven dimensions originally proposed by the Brazilian version of the OHIP-Edent. The interview analysis revealed new aspects related to phonetics, resilience, adaptive strategies, and pain management, that were not considered at the original OHIP-Edent. The comparison of quantitative and qualitative data analysis highlighted that the wording of some items could be confusing, while others were irrelevant to the respondents.
Conclusions: The present mixed-method study questioned the full validity of the Brazilian version of the OHIP-Edent. It supported the two interconnected dimensions of the OHIP-Edent, but it suggested the need for restructuring the questionnaire as it may not fully represent other deemed important aspects of quality of life of elderly Brazilians who are complete denture wearers.