Changes in parent‐assessed oral health‐related quality of life among young children following dental treatment under general anaesthetic

–  Objective:  To estimate the nature and magnitude of changes in oral health-related quality of life (OHRQoL) among children having dental treatment under general anaesthetic (GA) and to examine the evaluative properties of the Child Oral Health-related Quality of Life Questionnaire (COHQOL©). Methods:  Data from a consecutive clinical sample of the parents/caregivers of children receiving dental treatment under GA at Wellington and Kenepuru Hospitals were collected from parents using the Parental-Caregivers Perception Questionnaire (P-CPQ) and the Family Impact Scale (FIS), which both form part of the COHQOL© Questionnaire. The first questionnaire was completed before treatment or while the participant's child was undergoing treatment. The follow-up questionnaire was completed 1–4 weeks afterward. Treatment-associated changes in OHRQoL were determined by comparing baseline and follow-up data for the mean scores and the prevalence of impacts. The discriminative properties of the instrument were confirmed and then its evaluative properties were assessed (by examining its test–retest reliability, responsiveness and longitudinal construct validity). The minimally important difference was determined for the overall scale and subscales. Results:  Complete baseline and follow-up data were obtained for 202 and 130 participants, respectively (64.4% follow-up rate). The evaluative properties of the P-CPQ and FIS were acceptable. There were substantial and highly statistically significant reductions in mean P-CPQ and FIS scores after treatment, with effect sizes ranging from moderate to large, depending on the subscale being examined. The minimally important difference was shown by almost two-thirds of the children treated. Conclusion:  The provision of dental treatment under GA for young children with severe dental caries experience is associated with substantial and highly significant improvements in both their OHRQoL and in the impact on their families. The P-CPQ and the FIS show promise as evaluative measures for use in dental health services research.