2060. The Efficacy of Informed Consent in a Large Clinical Trial
JM Griffin, CCDOR, HB Rubins, CCDOR, JK Struve, CCDOR, A Liu, CCDOR, DB Nelson, CCDOR

Objectives: The goal of the informed consent process is for potential research participants to have a comprehensive understanding of the purpose for the study, the method of data collection, and the possible risks and benefits before making a voluntary decision to participate.  Little is known about how efficacious the process is, especially in large clinical trials, which, when conducted over a number of years, require a high degree of commitment from participants.  This study’s objective was to determine the long-term efficacy of informed consent in a large clinical trial and to evaluate how efficacy varies by participant characteristics.

Methods: Participants completing a multi-center VA cooperative studies program trial (VA-HIT) were asked three multiple-choice questions to assess their knowledge about the purpose of the study and its risks approximately 5 years after providing informed consent. Participants were asked: 1) the purpose of the study; 2) the study medication; and, 3) possible side effects from the medication. Demographic data were also collected. Answers were coded as correct or incorrect.  Multiple logistic regression models were used to estimate the relative odds of answering each question correctly, given the participants’ age, education, race, marital status, and their clinical site.

Results: Approximately 85% of the 2113 eligible participants completed the exit interview questions (n=1789).  The majority of the sample knew the main purpose of the study (51%) and the study medication (62%). Only 25% knew the main side effect of the medication.  In multivariate analyses, older and less educated participants had significantly lower odds of correctly answering questions about the study’s purpose and medication. Non-whites also had lower odds of correctly identifying the study’s purpose. Demographic characteristics did not differentiate clearly those who did and did not correctly answer question 3.

Conclusions: Older and less-educated participants were less likely to know the basic purpose and medication used in the study after five years of involvement. Non-whites were also less likely to know the purpose of the study.

Impact: Different types of presentation methods and materials, using simple, non-technical language is necessary to assure comprehension. Study participation requirements, risks, and benefits should also be addressed regularly throughout the course of a research study.