Clinical Trial Participation and Prescription Drug Use
- Presenter:
Chair: John Rizzo; Discussant: David Bradford Mon June 5, 2006 10:45-12:15 Room 213
Title: Clinical Trial Participation and Prescription Drug Use
Objective: To estimate the effect of cancer clinical trial participation on prescription drug utilization, drug costs, and out-of-pocket expenditures.
Methods: As part of the Cost of Cancer Treatment Study (CCTS), a national probability sample was drawn of patients participating in cancer clinical trials (n = 781) and a matched cohort of patients not enrolled in trials (n = 595) receiving treatment for the same cancers from the same providers as the trial participants. All CCTS subjects were interviewed about their prescription drug utilization and out-of-pocket drug expenditures. Treatment costs were estimated based on a large pharmacy transactions database. Multivariate regression was used to estimate the effects of trial participation on drug costs and out-of-pocket expenditures. Standard errors were corrected to account for the clustering of observations within trials and institutions. Weights were constructed using both propensity scores and sampling probabilities to correct for selection bias and to reflect the sampling design.
Results: Trial participation was associated with a $131 increase in prescription drug costs over a six-month period prior to the time of the interviews (p < 0.05), but no significant difference was found in out-of-pocket expenditures. These results were robust to a variety of model specifications.
Conclusions: Trial participation is associated with an increase in prescription drug utilization and costs, but these costs do not necessarily impose an economic burden on cancer trial participants.
