ASCPRO Recommendations for the Assessment of Fatigue as an Outcome in Clinical Trials

Context: Development of pharmacological and behavioral interventions for cancer-related fatigue (CRF) requires adequate measures of this symptom. A guidance document from the Food and Drug Administration offers criteria for the formulation and evaluation of patient-reported outcome measures used in clinical trials to support drug or device labeling claims. Methods: An independent working group, ASCPRO (Assessing Symptoms of Cancer Using Patient-Reported Outcomes), has begun developing recommendations for the measurement of symptoms in oncology clinical trials. The recommendations of the Fatigue Task Force for measurement of CRF are presented here. Results: There was consensus that CRF could be measured effectively in clinical trials as the sensation of fatigue or tiredness, impact of fatigue/tiredness on usual functioning, or as both sensation and impact. The ASCPRO Fatigue Task Force constructed a definition and conceptual model to guide the measurement of CRF. ASCPRO recommendations do not endorse a specific fatigue measure but clarify how to evaluate and implement fatigue assessments in clinical studies. The selection of a CRF measure should be tailored to the goals of the research. Measurement issues related to various research environments were also discussed. Conclusions: There exist in the literature good measures of CRF for clinical trials, with strong evidence of clarity and comprehensibility to patients, content and construct validity, reliability, and sensitivity to change in conditions in which one would expect them to change (assay sensitivity), and sufficient evidence to establish guides for interpreting changes in scores. Direction for future research is discussed.