What is the PRO-CTCAE Measurement System?

  • PRO-CTCAE is a patient-reported outcome (PRO) measurement system developed to evaluate symptomatic toxicity in patients on cancer clinical trials.
  • It was designed to be used as a companion to the Common Terminology Criteria for Adverse Events (CTCAE)External Web Site Policy, the standard lexicon for adverse event reporting in cancer clinical trials.
  • The PRO-CTCAE Item Library (PDF, 124 KB) includes 124 items representing 78 symptomatic toxicities drawn from the CTCAE.
  • A pediatric module permits self-reporting by children and adolescents ages 7-17 years (Ped-PRO-CTCAE® (PDF, 174 KB)) or caregiver-reporting for children ages 7-17 who are unable to self-report (Ped-PRO-CTCAE®[Caregiver] (PDF, 174 KB)). The pediatric module includes 130 items representing 62 symptomatic toxicities drawn from the CTCAE.
  • PRO-CTCAE and Ped-PRO-CTCAE items evaluate the symptom attributes of frequency, severity, interference, amount, presence/absence. Each symptomatic AE is assessed by 1-3 attributes.
  • Conditional branching logic can be implemented with electronic data capture for PRO-CTCAE and Ped-PRO-CTCAE or Ped-PRO-CTCAE [Caregiver], thereby reducing respondent burden.
  • PRO-CTCAE has been linguistically validated in more than 30 languages.
  • The Ped-PRO-CTCAE module was developed and tested in English in the U.S. and has been linguistically validated in Italian and Simplified Chinese. Several other languages are in development.


  • PRO-CTCAE and the Ped-PRO-CTCAE module are publicly available for all to use in their clinical research and we encourage and facilitate this use.
  • PRO-CTCAE and the Ped-PRO-CTCAE module should be used and reported in conjunction with the CTCAE reports gathered by clinicians. The PRO-CTCAE Measurement System provides additional information that is complementary to existing safety and tolerability assessments reported by clinicians using the CTCAE.
  • Item selection and timing of assessment are critical design decisions to reduce risk of bias and maximize interpretability and utility of results.
  • Choice of PRO-CTCAE and Ped-PRO-CTCAE module items is dependent upon anticipated adverse events based on previous preclinical data and regimen-specific information about the anticipated profile of symptomatic adverse events.
  • Timing of assessments:
    • Recall period for PRO-CTCAE and the Ped-PRO-CTCAE module is the past 7 days.
    • Consider weekly assessment during key periods in the trial (eg. first two cycles in an early phase trial) or at other crucial clinical assessment timeframes based upon knowledge of the anticipated toxicity profile of the regimen.
  • Once you have determined which symptomatic adverse events you wish to collect in your trial and at which timepoints of measurement, you can use our Form Builder to build a study-specific custom form.
  • PRO-CTCAE responses are scored from 0 to 4 (or 0/1 for absent/present).
  • Ped-PRO-CTCAE module responses are scored from 0 to 3 (or 0/1 for absent/present).
  • PRO-CTCAE and the Ped-PRO-CTCAE module yield up to three patient-reported scores per symptomatic toxicity.
  • There are as yet no standardized scoring rules for how to combine attributes into a single score or how best to analyze PRO-CTCAE data longitudinally.
Last Updated: 19 Apr, 2024