Under-representation of key demographic groups in opioid use disorder trials.
The extend to which clinical trials of medications for opioid use disorder (MOUD) are representative or not is unknown. Some patient characteristics modify MOUD effectiveness; if these same characteristics differ in distribution between the trial population and usual-care population, this could contribute to lack of generalizability — a discrepancy between trial and usual-care effectiveness. The objective of this study was to identify interpretable, multidimensional subgroups who were prescribed MOUD in substance use treatment programs in the US but who were not represented or under-represented by clinical trial participants.
This study was a secondary descriptive analysis of trial and real-world data. The trial data included 27 US opioid treatment programs in the NIDA National Drug Abuse Treatment Clinical Trials Network (CTN-0027, CTN-0051, and CTN-0030), N=2,199 patients. The real-world data included US substance use treatment programs that receive public funding, N=740,015 patients (TEDS-A data). The authors characterized real-world patient populations who were non-represented and under-represented in the trial data in terms of sociodemographic and clinical characteristics that could modify MOUD effectiveness.
The authors found that 10.7% of MOUD patients in TEDS-A (real-world sample) were not represented in the three clinical trials. As expected, pregnant MOUD patients (n=19,490) were not represented. Excluding pregnancy, education, and marital status from the characteristics, 2.6% of MOUD patients were not represented. Patients aged 65 years and older (n=11,204) and those 50-64 years who identified as other (non-white, non-Black, and non-Hispanic) race/ethnicity or multi-racial (n=7,281) were under-represented.
Conclusions: Quantifying and characterizing non- or under-represented subgroups in trials can provide the data necessary to improve representation in future trials and address research-to-practice gaps.
Related protocols: CTN-0027, CTN-0030, CTN-0051