Quality of life of pediatric oncology patients: Do patient-reported outcome instruments measure what matters to patients?

Purpose: The assessment of quality of life (QOL) is key within pediatric oncology and requires a clearly defined construct of QOL. The purpose of our study was: (1) to conduct a qualitative study to inform the theoretical underpinnings of QOL and (2) to determine the appropriateness of patient-reported outcome (PRO) instruments to assess and evaluate QOL in pediatric cancer patients and survivors.

Methods: The study used an interpretative description approach. Children diagnosed with childhood cancer, aged 8-18 years, were recruited from four Canadian hospitals. Semi-structured interviews were completed, transcribed verbatim and coded through methods of constant comparison. In-depth analysis facilitated a comparison between emerging themes and the content of commonly used PRO instruments.

Results: Thirty-seven children (19 females; 51 %) participated. The mean age was 13 years, and 19 (51 %) participants were post-treatment. Participant experiences reflected notions of positive and negative duality, including: maintaining physical functioning but longing for the ability to participate in activities; experiencing a new level of intimacy with family and friends amidst isolation; and developing positivity amidst anger, sadness and lingering worry. Analysis showed that existing PRO instruments are missing concerns specific to this population and contain content not reflective of the QOL experiences of childhood cancer patients and survivors.

Conclusions: Our research highlights important problems with content validity of existing PRO scales, indicating that the tools we have to date have limited utility in research and clinical practice. The development of a new PRO instrument should be considered to ensure that content validity is achieved.