Do noncontingent vouchers increase drug use?
Data from 2 contingency management trials, targeting opiate or cocaine use, were used to investigate whether noncontingent vouchers inadvertently reinforce drug use. The control group in each trial received noncontingent vouchers matched in value and frequency to those received by experimental groups, but independent of urinalysis. Vouchers were offered thrice weekly for 8 weeks (opiates) or 12 weeks (cocaine). Both dose-response and temporal associations of noncontingent voucher receipt with drug-positive urines were assessed. Drug use was unrelated to frequency of noncontingent voucher delivery and noncontingent voucher receipt when being drug positive was unassociated with risk of subsequent drug use, with one exception: cocaine use in the cocaine study (relative risk = 1.05, 95% confidence interval: 1.01-1.09). Overall, results do not indicate a causal relationship between noncontingent voucher receipt and increased drug use.
Schroeder
Jennifer R
JR
Intramural Research Program, National Institute on Drug Abuse, National Institutes of Health, Baltimore, Maryland 21224, USA. jschroed@intra.nida.nih.gov
Gupman
Anne E
AE
Epstein
David H
DH
Umbricht
Annie
A
Preston
Kenzie L
KL
D000328:Adult; D019970:Cocaine-Related Disorders / Q000523:psychology* / Q000534:rehabilitation / Q000652:urine; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008691:Methadone / Q000627:therapeutic use; D009294:Narcotics / Q000627:therapeutic use; D009293:Opioid-Related Disorders / Q000523:psychology* / Q000534:rehabilitation / Q000652:urine; D011569:Psychiatric Status Rating Scales; D012008:Recurrence; D018570:Risk Assessment; D015813:Substance Abuse Detection; D019966:Substance-Related Disorders / Q000523:psychology* / Q000534:rehabilitation / Q000652:urine; D016896:Treatment Outcome
D009294:Narcotics; D008691:Methadone