WHAT DIFFERENCE DOES IT MAKE TO BE TREATED IN A CLINICAL-TRIAL - A PILOT-STUDY

Objective: Pilot study to characterize treatment differences between p atients treated in clinical trials and those treated in a clinical set ting. Previous studies have shown higher survival rates for participan ts in trials of cancer therapy. This difference is observed even after rates are adjusted for important covariates such as age and stage of disease. Design: Retrospective chart review. Setting: Oncology outpati ent department in a tertiary care hospital. Patients: Ninety women 18 to 70 years of age with early-stage breast cancer who were diagnosed i n 1990. Fifty-one of the women were treated through clinical trials an d 39 were treated outside of clinical trials. Outcome measures: Number of blood tests, telephone calls, clinic visits and imaging procedures as well as intensity of chemotherapy and use of radiation therapy. Th e age of the patient. and the stage of disease were important covariat es. Results: After the analysis was controlled for patient age and sta ge of disease, patients treated through a clinical trial were more lik ely to receive standard-dose chemotherapy (p = 0.020, 95% confidence i nterval 1.20 to 200.73) and more frequent blood tests (p < 0.001, 95% confidence interval 1.02 to 1.13) than other patients treated in the c linic. Conclusions: Our results provide a plausible mechanism for the observed survival advantage for participants in clinical trials in onc ology. Further study is called for. If these results are confirmed, th ey have important implications for informed consent to participate in clinical trials and for clinical practice.