September 2006

Objective To validate the Japanese version of the Oral Health Impact Profile (OHIP-J) for use among young and middle-aged adults. Evaluating the criterion validity was particularly important in this study. Method The original Oral Health Impact Profile (OHIP) was translated into Japanese. Data from 6,079 subjects aged 20-59 were collected by means of a self-administered questionnaire and the oral condition records of a sample of workers. The survey involved items for the OHIP-J and self-rated oral health, denture wearing, number of missing teeth, work type, occupational rank, gender, and age. We adopted a self-rated oral health and number of missing teeth as validity criteria for this analysis. Results Using multiple linear regression analysis, the adjusted total OHIP-J scores for respondents who rated their oral health as poor were higher than those who did not (46.6 vs. 27.6; p<0.001). The variable of missing teeth was significantly associated with the OHIP-J total and subscale scores independent of gender, age and denture wearing (p<0.001). Conclusions These findings suggest that the OHIP-J is suitable for assessing the oral health-related quality of life of young and middle-aged adults in Japan. Key words: oral health; quality of life; questionnaire; validity