Addiction treatment trials: how gender, race/ethnicity, and age relate to ongoing participation and retention in clinical trials.
BACKGROUND
Historically, racial and ethnic minority populations have been underrepresented in clinical research, and the recruitment and retention of women and ethnic minorities in clinical trials has been a significant challenge for investigators. The National Drug Abuse Treatment Clinical Trials Network (CTN) conducts clinical trials in real-life settings and regularly monitors a number of variables critical to clinical trial implementation, including the retention and demographics of participants.


OBJECTIVE
The examination of gender, race/ethnicity, and age group differences with respect to retention characteristics in CTN trials.


METHODS
Reports for 24 completed trials that recruited over 11,000 participants were reviewed, and associations of gender, race/ethnicity, and age group characteristics were examined along with the rate of treatment exposure, the proportion of follow-up assessments obtained, and the availability of primary outcome measure(s).


RESULTS
Analysis of the CTN data did not indicate statistical differences in retention across gender or race/ethnicity groups; however, retention rates increased for older participants.


CONCLUSIONS
These results are based on a large sample of patients with substance use disorders recruited from a treatment-seeking population. The findings demonstrate that younger participants are less likely than older adults to be retained in clinical trials.
Division of Biostatistics and Epidemiology, Medical University of South Carolina, Charleston, SC, USA.
Jeffrey E
JE
Korte
Center for the Clinical Trials Network, National Institute on Drug Abuse, Bethesda, MD, USA.
Carmen L
CL
Rosa
Center for the Clinical Trials Network, National Institute on Drug Abuse, Bethesda, MD, USA.
Paul G
PG
Wakim
Center for the Clinical Trials Network, National Institute on Drug Abuse, Bethesda, MD, USA.
Harold I
HI
Perl
addiction treatment; age; clinical trials; ethnic minorities; gender difference; race; recruitment; retention; substance use disorders