Does enrollment in a randomized clinical trial lead to a higher cost of routine care?

Reimbursement for the routine care of patients enrolled in clinical trials is controversial. Our objective was to determine the added medical costs, if any, associated with enrollment in a randomized clinical trial.

We analyzed data from the Myocardial Infarction Triage and Intervention (MITI) Trial (1988-1991) and the registry of all patients admitted to 19 Seattle area coronary care units (1988-1993). The major trial entry criteria were age 35 to 71 years, symptom duration 15 minutes to 6 hours, and acute myocardial infarction on electrocardiogram. The trial group consisted of 264 of 324 randomized patients who received thrombolytics and had available cost data. From 11,932 registry patients, we identified a control group who met trial entry criteria but who were not enrolled because of logistic barriers or presentation outside the trial enrollment period, 335 of whom received thrombolytics and had available cost data. The groups were compared for total cost for initial hospitalization, with and without multivariable adjustment for baseline characteristics.

Total hospital cost was not different between trial patients (median $11,516) and control subjects (median $14,200) (trial/control mean cost ratio 0.91 [95% CI 0.82-1.02]). Participation in the trial had an insignificant effect on costs in the multivariable model (cost ratio 1.04, 95% CI 0.95-1.16). Significant predictors of cost included hospital of admission, length of stay, and coronary revascularization procedures.

Participation in the MITI randomized trial had no effect on the cost of routine care.