The PedsQL™ Present Functioning Visual Analogue Scales:: preliminary reliability and validity

Background: The PedsQL(TM) Present Functioning Visual Analogue Scales ( PedsQL T VAS) were designed as an ecological momentary assessment (EMA) instrument to rapidly measure present or at-the-moment functioning in children and adolescents. The PedsQL(TM) VAS assess child self-report and parent-proxy report of anxiety, sadness, anger, worry, fatigue, and pain utilizing six developmentally appropriate visual analogue scales based on the well-established Varni/Thompson Pediatric Pain Questionnaire (PPQ) Pain Intensity VAS format. Methods: The six-item PedsQL(TM) VAS was administered to 70 pediatric patients ages 5 - 17 and their parents upon admittance to the hospital environment ( Time 1: T1) and again two hours later ( Time 2: T2). It was hypothesized that the PedsQL(TM) VAS Emotional Distress Summary Score ( anxiety, sadness, anger, worry) and the fatigue VAS would demonstrate moderate to large effect size correlations with the PPQ Pain Intensity VAS, and that patient" parent concordance would increase over time. Results: Test-retest reliability was demonstrated from T1 to T2 in the large effect size range. Internal consistency reliability was demonstrated for the PedsQL(TM) VAS Total Symptom Score ( patient self-report: T1 alpha =.72, T2 alpha =.80; parent proxy-report: T1 alpha =.80, T2 alpha =.84) and Emotional Distress Summary Score ( patient self-report: T1 alpha =.74, T2 alpha =.73; parent proxy-report: T1 alpha =.76, T2 alpha =.81). As hypothesized, the Emotional Distress Summary Score and Fatigue VAS were significantly correlated with the PPQ Pain VAS in the medium to large effect size range, and patient and parent concordance increased from T1 to T2. Conclusion: The results demonstrate preliminary test-retest and internal consistency reliability and construct validity of the PedsQL T Present Functioning VAS instrument for both pediatric patient self-report and parent proxy-report. Further field testing is required to extend these initial findings to other ecologically relevant pediatric environments.