Linguistic and content validation of a German-language PRO-CTCAE-based patient-reported outcomes instrument to evaluate the late effect symptom experience after allogeneic hematopoietic stem cell transplantation

Purpose: The aim of this sequential mixed methods study was to develop a PRO-CTCAE (Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events)-based measure of the symptom experience of late effects in German speaking long-term survivors of allogeneic stem cell transplantation (SCT), and to examine its content validity.

Methods: The US National Cancer Institute's PRO-CTAE item library was translated into German and linguistically validated. PRO-CTCAE symptoms prevalent in ≥50% of survivors (n = 15) and recognized in its importance by SCT experts (n = 9) were identified. Additional concepts relevant to the symptom experience and its consequences were elicited. Content validity of the PROVIVO (Patient-Reported Outcomes of long-term survivors after allogeneic SCT) instrument was assessed through an additional round of cognitive debriefing in 15 patients, and item and scale content validity indices by 9 experts.

Results: PROVIVO is comprised of a total of 49 items capturing the experience of physical, emotional and cognitive symptoms. To improve the instrument's utility for clinical decision-making, questions soliciting limitations in activities of daily living, frequent infections, and overall well-being were added. Cognitive debriefings demonstrated that items were well understood and relevant to the SCT survivor experience. Scale Content Validity Index (CVI) (0.94) and item CVI (median = 1; range 0.75-1) were very high.

Conclusions: Qualitative and quantitative data provide preliminary evidence supporting the content validity of PROVIVO and identify a PRO-CTCAE item bundle for use in SCT survivors. A study to evaluate the measurement properties of PROVIVO and to examine its capacity to improve survivorship care planning is underway.