Which aspects of an oral health-related quality of life measure are mainly associated with global ratings of oral health in children?

Objectives To assess the associations of global subjective ratings of oral health with different aspects of an oral health-related quality of life measure, namely total Oral Impacts on Daily Performances (OIDP) and Child-Oral Impacts on Daily Performances (Child-OIDP) scores, extent and intensity of oral impacts, the different performance scores and oral impacts attributed to certain groups of oral conditions. Methods This study was part of the Sixth Thailand National Oral Health Survey. One thousand and sixty-six 12-year-olds and 815 15-year-olds were interviewed on their OHRQoL using Child-OIDP and OIDP indices, respectively, and rated their overall oral problems on 3-point and 5-point scales, respectively. Associations of global rating of oral health with different Child-OIDP/OIDP outcome variables were estimated using Spearman's rank correlations and logistic regressions. Results Child-OIDP/OIDP scores were significantly associated with global ratings. Intensity was associated with global ratings, whereas extent was not. Impacts of 'very little' intensity were associated with a slightly higher chance of having poorer oral health perceptions. Global ratings were associated most with oral impacts attributed to dental caries, but not with the impacts related to natural process, such as eruption. Eating, cleaning teeth, emotional stability and smiling, plus social contact in 15-year-olds were performances associated with global ratings. Fifteen-year-old girls were more likely to perceive more oral problems than boys. Conclusions Associations of global ratings of oral health with Child-OIDP/OIDP scores were mainly due to the intensity of impacts. Global ratings were related to multidimensional aspects of children's quality of life.