Last update:
02-Oct-2009

OBJECTIVE The growing recognition that quality of life (QoL) is an important outcome of dental care has created a need for the development of specific instruments to measure oral health related quality of life. The oral health impact profile short form (OHIP-14) and the oral impacts on daily performances (OIDP) are two of the most commonly used instruments. This study aimed to evaluate oral health related QoL (OHR-QoL) of dental patients in the General Hospital of Kalymnos in relation to sociodemographic factors and clinical variables, and in addition to evaluate and compare two OHR-QoL measures in terms of validity and reliability.

METHOD Data were collected from 335 patients aged 18-65+ years by personal interview and clinical examination. Sex, age, educational level, reason for dental visit, self-rated oral health and mouth appearance, bad breath (halitosis), DMFT index, periodontal status, missing teeth and prosthodontic restoration were the independent variables used in the statistical analysis model. Both scores from the two QoL instruments were the dependent variables. Construct validity was evaluated in terms of comparisons between groups. OIDP was the reference instrument to evaluate criterion related validity of OHIP-14. Reliability was evaluated in terms of internal consistency using Cronbach's coefficient α.

RESULTS The oral health status of the study population was moderate to low. OHR-QoL was found to be fairly satisfactory. Correlations between scores and independent variables (except the variable "sex") were statistically significant (P<0.01) and in the expected direction. Both questionnaires discriminated between different groups. DMFT index and self-rated oral health and mouth appearance explained the variation in OHR-QoL to a greater degree than the other variables. OHIP-14 and OIDP scores were strongly correlated (rs=0.94), while Cronbach's coefficient α was 0.92 and 0.84, respectively.

CONCLUSIONS One clinical index (DMFT index) and two subjective variables (self-ratings about oral health and mouth appearance) are determinants of OHR-QoL. Both questionnaires showed very good psychometric properties.

Key words: Oral health, Quality of life, Questionnaires.