Exploration of the Reliability and Validity of a Short form of the Oral Health Impact Profile for Prostheses

Abstract

Purpose: The Oral Health Impact Profile (OHIP) is one of the most widely used instruments to measure oral health-related quality of life (OHRQoL). The aim of this study was to evaluate the reliability and validity of a Japanese short version of the Oral Health Impact Profile (OHIP-JP16) for prostheses.Methods: Data were collected by means of self-administered questionnaires from July 2004-November 2005 at 4 dental offices located in Japan. The questionnaires consisted of self-perceived oral health status, need for treatment, and the OHIP-JP16 score. The total target sample consisted of 137 patients, of which 125 patients answered all the 16 items in the questionnaires. The reliability was assessed in terms of internal consistency and reproducibility.Results: Cronbach’s alpha of the OHIP-JP16 subscales ranged from 0.43 to 0.93. The reproducibility of test-retest reliability was analyzed (n=12). The test-retest reliability was measured by the intra-class correlation coefficient (ICC) and kappa index. The ICC ranged from 0.69-0.92 and kappa index ranged from 0.12-0.67. The internal consistency and reproducibility demonstrated quite a good reliability. Discriminative validity was examined by comparing total scores among groups according to the following parameters: number of teeth (more than 24 and less than 23), Eichner index (A, B, and C group), denture wearing (with and without dentures), and self-perceived oral health (good and poor). The patients who had more than 24 teeth, were in group A of the Eichner index, those without dentures, and having good oral health had better OHIP-JP16 total scores (P<0.05).Conclusion: As a result of having examined for behaviormetrics study, OHIP-JP16 showed good measurement properties and might be appropriate for use in the clinical settings.