Background/Purpose:

There is a current need to integrate health related quality of life (HRQoL) into outcomes for clinical trials (Chang & Reeve, 2005). For pediatric localized scleroderma (LS), large gaps continue to exist in regards to the impact of LS on QoL, and clinical trials have been limited by the lack of valid patient-reported outcomes (PROs). Our group developed the pediatric LS Quality of Life Instrument (LoSQI) to meet this need. The LoSQI includes 3 domains (skin sensations, physical functioning, body image and social support) and an optional subscale (systemic medication side effects). The goal of this project was to provide validity evidence for the LoSQI scores in children with LS.

Methods:

The study had two phases (1) a pilot study and (2) a field test. The main purpose of the pilot study was to obtain input from pediatric LS patients regarding the under- and over- representation of the included content domains, understandability and readability of the survey items, and appropriateness of the recall period. Semi-structured interviews were used. The main goal of the field test was to provide quantitative validity evidence from multiple sources including patterns of missing or skipped items, reliability coefficients, and convergent and divergent validity. Patients were recruited from specialized scleroderma clinics at two sites: the Children’s Hospital of Pittsburgh and the UT Southwestern Medical Center.

Results:

Seventeen patients (ages 8-17) were enrolled into the pilot study and 74 patients aged 11-20 years were enrolled for the field test. Only 4% of the sample (3/74) had missing or skipped items. Internal consistency was excellent (all coefficients >0.8; Table 1) and test re-test reliability was >0.7 for the total score. The LoSQI had moderate to strong relationships with other PROs, but limited correlations with physician reported measures of disease activity and damage (Table 2).

Conclusion:

Initial evidence supports the reliability and validity of the LoSQI to measures HRQoL in pediatric patients. Limited correlations to physician reported outcomes suggest that the LoSQI measures unique information and should be an additional outcome measured in future clinical trials. Additional examination into the responsiveness of the scale to change is needed.

Table 1. Reliability coefficients for LoSQI.

Table 2. Relationships of the LoSQI total score to patient, parent, and physician reported outcomes.

CDLQI/DLQI = Children’s Dermatology Life Quality Index; VAS = Visual Analogue scale; mLoSSI = Localized Scleroderma Skin Severity Index; LoSDI = Localized Scleroderma Damage Index; PGA= Physician Global Assessment.