Applicability of an abbreviated version of the oral impacts on daily performances (OIDP) scale for use among Tanzanian students

Objectives: The objective was to examine the applicability of an abbreviated version of the oral impact of daily performances (OIDP) inventory to Tanzanian adults attending the University of Dar es Salaam. Method: A total of 1123 students (mean age 26.4 years, response rate 58%) completed a survey instrument designed to measure subjective oral health indicators including the eight-item OIDP frequency scores. After a period of 4 weeks, 228 students (mean age 24.6 years, response rate 65%) were examined clinically for the presence or absence of oral disorders. Results: A total of 51% of the participants reported that an oral problem had affected them on at least one daily performance in the 6 months preceding the survey. Cronbach's alpha for the OIDP frequency items was 0.83 and 0.87 on the first and second administration of the questionnaire. A reliability coefficient (Spearman's rho) of 0.87 was obtained for the OIDP frequency scores. For five of the eight OIDP frequency items, the kappa values ranged from 0.60 to 1.0, whereas one scale item had the less satisfactory value of 0.22. Construct validity was demonstrated in that the OIDP frequency scores were statistically significantly associated in the expected direction with clinically observed oral problems and a global self-report indicator of oral health status, respectively. Conclusion: The OIDP frequency scale seems to have acceptable psychometric properties in the context of a descriptive questionnaire survey among Tanzanian university students.