Clinical trials employ a variety of approaches to measure the
health status of patients and changes in their health due to
treatment. In many therapy areas, subjective ratings made
by the patient or by a clinician are used to measure status or
change over time. Patient-reported outcomes measures, such
as a daily symptom diary or a quality of life questionnaire,
importantly measure the perspective of the patient
regarding the effects of treatment, and in some cases (e.g.
pain assessment) may be the only way to assess outcomes.
Bill Byrom, Darragh Walsh and Willie Muehlhausen of
ICON Clinical Research discuss a further clinical outcome
assessment, which is the performance outcome (PerfO), in this
article.