Determinants of children's oral-health-related quality of life over time.

OBJECTIVE: To identify clinical and psychosocial predictors of oral-health-related quality of life (OHQoL) in Thai children over time. METHODS: OHQoL data were collected from 510 students aged 10-14 years at baseline and 3, 6 and 9-month follow-up using the Child Perceptions Questionnaire (CPQ11-14), and sense of coherence (SOC), dental coping beliefs (DCB) and socioeconomic status (maternal educational attainment, paternal educational attainment and parental income), together with clinical variables (untreated caries, gingival health, malocclusion, dental opacities), were collected at baseline. The data were analysed with structural equation modelling (SEM) guided by the Wilson and Cleary model (J Am Med Assoc 1995;273:59). RESULTS: Mean DMFT was 1.97 (SD=1.81). Most students had healthy gingivae (54.3%) and 68.9% scored IOTN 1-4. The SEM model fitted the data well [CMIN/DF=2.574, SRMR=0.0561, CFI=0.974 and RMSEA=0.059 (90% CIs=0.039-0.079)]. Higher SOC, DCB and socioeconomic status (SES) at baseline consistently predicted better OHQoL at all three time points. Untreated caries at baseline predicted worse OHQoL at 6-month follow-up only. Malocclusion and dental opacities were unrelated to OHQoL at any time point. CONCLUSIONS: Individual factors, particularly SOC, were important influences on OHQoL, suggesting that interventions designed to promote SOC may present an opportunity to enhance children's experience of oral health in their daily lives. Clinical factors were not consistently related to OHQoL. This could be attributed to weak relationships between the two, the low level of disease and/or the sensitivity and discriminant validity of the CPQ11-14.