Objectives: To assess the agreement between mothers and children concerning the child's oral health-related quality of life.
Methods: A total of 42 pairs of mothers and children aged 11–14 years with oral and orofacial conditions completed the parental (PPQ) and child (CPQ11–14) components of the Child Oral Health Quality of Life Questionnaire. The PPQ and CPQ11–14 are analogous questionnaires with 31 common items. Agreement between overall and subscale scores derived from the questionnaires were assessed in comparison and in correlation analyses. The former used mean directional differences between mothers and children to assess bias and mean absolute differences to assess agreement at the group level. The latter used intraclass correlation coefficients (ICCs) to assess agreement at the level of individual mother–child pairs.
Results: At the group level, agreement between mothers and children was good. There was little evidence of bias in mothers' reports compared to those of their children. The mean absolute difference in overall scores constituted 9% of the possible range of scores. However, the significance of this difference is difficult to interpret. The ICC for overall scores was 0.70 indicating substantial agreement between mother and child pairs. However, the ICCs for the emotional and social well-being subscales indicated moderate agreement only. There was a suggestion that the level of agreement varied according to the characteristics of the child.
Conclusion: Although mothers may be used as proxies for their children in some circumstances and for some purposes, the views of both should be obtained in order to fully represent child oral health-related quality of life.