What Do 'None,' 'Mild,' 'Moderate,' 'Severe,' and 'Very Severe' Mean to Patients With Cancer? Content Validity of PRO-CTCAE™ Response Scales

Accurate capture of the symptom experience is essential to gauging efficacy, safety, and tolerability of cancer treatments. The Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) was developed by the National Cancer Institute to allow direct patient self-reporting of symptomatic adverse events in cancer clinical trials. Its content validity has been established in accordance with recommended practices for novel patient-reported outcome (PRO) instruments.