IADR Abstract Archives
Valuation of CARIES-QC-U: a Child-Centred Caries-Specific Preference-Based Measure
Objectives: Dental caries has significant impacts on children’s daily lives. Whilst interventions are available to improve children’s oral health, there is a clear need for a preference-based measure (PBM) that is able to generate Quality Adjusted Life Years (QALYs) in economic evaluations of these interventions. This study aimed to develop a child-centred PBM, through adaptation of CARIES-QC (Caries Impacts and Experiences Questionnaire for Children), a caries-specific measure of oral health-related quality of life.
Methods: Ethical approval was obtained for this study. A five-item classification system that the authors derived from CARIES-QC using Rasch analysis, psychometric testing and involvement of stakeholders, and validated with children, was used as the basis for the PBM. Two online surveys were created to elicit preferences for the classification system; a best-worst scaling (BWS) survey for completion by adolescents aged 11-16 years and a modified discrete choice experiment (DCETTO) survey for completion by adults over 18 years. Preferences were modelled using the conditional logit model. Mapping regressions were used to anchor the adolescent BWS data onto the QALY scale using adult DCETTO values, since the BWS survey data alone cannot generate anchored values.
Results: Representative samples of 723 adolescents and 626 adults from across the UK completed the surveys. Fully consistent (as health worsened, health state value worsened) and robust models were produced for both BWS and DCETTO data. The BWS preferences were mapped onto the DCETTO values, resulting in an algorithm able to estimate a utility value for each health state defined by the classification system, enabling QALYs to be generated.
Conclusions: This PBM, known as CARIES-QC-U (for Utility), is the first to be developed specifically for use in child oral health research. The mapped estimates can be used to generate QALYs in economic evaluations of interventions to improve children’s oral health.
Methods: Ethical approval was obtained for this study. A five-item classification system that the authors derived from CARIES-QC using Rasch analysis, psychometric testing and involvement of stakeholders, and validated with children, was used as the basis for the PBM. Two online surveys were created to elicit preferences for the classification system; a best-worst scaling (BWS) survey for completion by adolescents aged 11-16 years and a modified discrete choice experiment (DCETTO) survey for completion by adults over 18 years. Preferences were modelled using the conditional logit model. Mapping regressions were used to anchor the adolescent BWS data onto the QALY scale using adult DCETTO values, since the BWS survey data alone cannot generate anchored values.
Results: Representative samples of 723 adolescents and 626 adults from across the UK completed the surveys. Fully consistent (as health worsened, health state value worsened) and robust models were produced for both BWS and DCETTO data. The BWS preferences were mapped onto the DCETTO values, resulting in an algorithm able to estimate a utility value for each health state defined by the classification system, enabling QALYs to be generated.
Conclusions: This PBM, known as CARIES-QC-U (for Utility), is the first to be developed specifically for use in child oral health research. The mapped estimates can be used to generate QALYs in economic evaluations of interventions to improve children’s oral health.