Selecting PedsQL items to derive the PedsUtil health state classification system to measure health utilities in children.

Background: There is a lack of preference-based health-related quality of life (HRQoL) measures that consistently value health across a full range of child age groups. The PedsQL is a generic HRQoL instrument validated for children 2-18 years, but it is not preference-based. The objective of this study was to derive the PedsUtil health state classification system from the PedsQL as a basis for a preference-based HRQoL measure for children.

Methods: A two-step process was used to select PedsQL items to include in the health state classification system: 1) exclude poorly functioning items according to Rasch analysis in each of the previously established seven dimensions of the PedsUtil health state classification system and 2) select a single item to represent each dimension based on Rasch and psychometric analyses, as well as input from child health experts and parents. All secondary analyses were conducted using data from the Longitudinal Study of Australian Children (LSAC). Analyses were stratified by age group (i.e., 2-5 years, 6-13 years, and 14-17 years) to represent the different developmental stages of children and to reflect the study design of the LSAC. Rasch analyses were also performed on five random subsamples for each age group to enhance robustness of results.

Results: Twelve items were excluded from the PedsUtil health state classification system after the first step of the item selection process. An additional four items were excluded in the second step, resulting in seven items that were selected to represent the seven dimensions of the PedsUtil health state classification system: Physical Functioning ("participating in sports activity or exercise"), Pain ("having hurts or aches"), Fatigue ("low energy level"), Emotional Functioning ("worrying about what will happen to them"), Social Functioning ("other kids not wanting to be their friend"), School Functioning ("keeping up with schoolwork"), and School Absence ("missing school because of not feeling well").

Conclusions: The PedsUtil health state classification system was derived from the PedsQL based on several criteria and was constructed to be applicable to children two years and older. Research is ongoing to elicit preferences for the PedsUtil health state classification system to construct the PedsUtil scoring system.