Generalizability of clinical trials for cannabis dependence to community samples

• Published in: Drug and alcohol dependence Vol. 111; no. 1; pp. 177 - 181
• Main Authors: Okuda, Mayumi, Hasin, Deborah S, Olfson, Mark, Khan, Sharaf S, Nunes, Edward V, Montoya, Ivan, Liu, Shang-Min, Grant, Bridget F, Blanco, Carlos
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 01.09.2010; Elsevier
• Subjects: Addictive behaviors; Adolescent; Adult; Adult and adolescent clinical studies; Biological and medical sciences; Cannabis; Cannabis dependence; Clinical standards; Clinical trials; Clinical Trials as Topic; Drug addiction; Drug dependency; Eligibility; Eligibility criteria; Epidemiology; Exclusion criteria; Female; General aspects; Generalizability; Humans; Inclusion criteria; Male; Marijuana Abuse - epidemiology; Marijuana Smoking - epidemiology; Medical sciences; Miscellaneous; Patient Selection; Psychiatry; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Public health. Hygiene; Public health. Hygiene-occupational medicine; Exclusion criteria; Generalizability; Inclusion criteria; Clinical trials; Eligibility criteria; Epidemiology; Cannabis dependence; Cannabidaceae; Generalization; Cannabis; Criterion; Dicotyledones; Angiospermae; Dependence; Clinical trial; Drug of abuse; Public health; Human; Drug addiction; Sample; Extrapolation; Addiction; Spermatophyta; Community; Recreational drug
• ISSN: 0376-8716; 1879-0046
• DOI: 10.1016/j.drugalcdep.2010.04.009

Abstract There is growing concern that results of tightly controlled clinical trials may not generalize to broader community samples. To assess the proportion of community dwelling adults with cannabis dependence who would have been eligible for a typical cannabis dependence treatment study, we applied a standard set of eligibility criteria commonly used in cannabis outcome studies to a large ( N = 43,093) representative US adult sample interviewed face-to-face, the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). Approximately 80% of the community sample of adults with a diagnosis of cannabis dependence ( N = 133) would be excluded from participating in clinical trials by one or more of the common eligibility criteria. Individual study criteria excluded from 0% to 41.0% of the community sample. Legal problems, other illicit drug use disorders, and current use of fewer than 5 joints/week excluded the largest percentage of individuals. These results extend to cannabis dependence concerns that typical clinical trials likely exclude most community dwelling adults with the disorder. The results also support the notion that clinical trials tend to recruit highly selective samples, rather than adults who are representative of typical patients. Clinical trials should carefully evaluate the effects of eligibility criteria on the generalizability of their results. Even in efficacy trials, stringent exclusionary criteria could limit the representativeness of study results.