17 - Practical considerations in outcomes assessment for clinical trials

Summary

While clinical outcomes are often the primary method of evaluation in clinical trials, endpoints requiring patient-reported measures are essential. The scientific literature is full of reports where investigators make logical but unsubstantiated claims of quality-of-life benefits to patients based on the assumption that a change in treatment or a traditional biomedical outcome will improve the patient's quality of life. While in many cases this may be true, surprising results are sometimes obtained when the patient is asked directly. One classic example occurred with a study by Sugarbaker et al. comparing two therapeutic approaches for soft-tissue sarcoma. The first was limb-sparing surgery followed by radiation therapy. The second treatment approach was full amputation of the affected limb. The investigator hypothesized that “Sparing a limb, as opposed to amputating it, offers a quality of life advantage.” Rather than assuming this was true, the investigators tested their hypothesis. Subjects who received the limb-sparing procedures reported limitations in mobility and sexual functioning. These observations were confirmed with physical assessments of mobility and endocrine function. As a result of these studies, the original hypothesis was rejected, radiation therapy was modified, and physical rehabilitation was added to the limb-sparing therapeutic approach.

There is a danger of adding patient-based outcomes to every clinical trial. If the majority of these studies either fail to answer clinically relevant questions or are methodologically weak, eventually a negative perception about patient-centered outcomes will grow in the research community.