Search the Library
NOTE: This is a new search platform (as of May 2026). If you do a search and don’t get the results you were expecting, please email us at ctnlib@uw.edu to let us know? (If possible, please share your exact search strategy. Thank you!)
Enter keywords and hit Enter (or click the magnifying glass) to search. You can then also select document type or subject/topic to narrow results further (or just use those for searching without a keyword). Results display below this search form.
Document types
Subjects
- CTN-#### format for protocols (CTN-0001, e.g.)
- “exact phrase” (if phrase is not found, it will return results that contain all terms
- word1 NOT word2
- word1 word2 (finds both words)
- Click title to access full-text
- “Show details” reveals abstract & other info
- Checkboxes select items for copy/pasting or printing
- Need help getting a copy of a journal article?
Email ctnlib@uw.edu
Search results

Cocaine use disorder (CUD) is a major public health issue, and greater cocaine use severity has been associated with worse treatment retention and outcomes. Therefore, greater understanding of processes that influence cocaine use is needed. Both anhedonia (i.e., undervaluation of nondrug rewards) and cocaine demand (i.e., cocaine valuation) are related to cocaine use severity and thematically related to each other at face value, but no studies have directly compared these outcomes to our knowledge.
The present study represents a secondary analysis from a two-phase sequential, multiple assignment, randomized trial aimed at developing adaptive interventions for CUD (CTN-0130). We examined the relationship between anhedonia and cocaine demand and how these measures were related to cocaine use severity. Participants (N = 116) were treatment-seeking adults with CUD. All measures were taken at baseline before treatment initiation. Analyses revealed (a) moderate and very strong evidence of relationships between cocaine demand factors (i.e., persistence, amplitude) and anhedonia (PP values ≥ 77.8%); (b) positive association between cocaine demand (both persistence and amplitude) and measures of cocaine use severity, with the exception of one relationship, which was in the opposite direction; and (c) demand amplitude continued to be positively related to cocaine use severity, even when considering anhedonia.
Conclusions: Overall, findings from this study indicate cocaine demand relates to cocaine use severity more strongly than anhedonia.
Related protocols: CTN-0130

This is the Primary Outcomes Article for CTN-0130.
Fentanyl-related, cocaine-overdose deaths have drastically increased, yet research on how people who use cocaine perceive fentanyl adulteration is limited. This study developed the novel Adulterated Cocaine Purchasing Task, a modification of the original Cocaine Purchasing Task, to quantify how people respond to fentanyl adulteration in cocaine.
In the Adulterated Cocaine Purchasing Task, participants indicated how much cocaine they would purchase when cocaine had no (0%) versus some (10%) probability of fentanyl adulteration. Study aims were to (a) determine how possible fentanyl adulteration affects cocaine demand and (b) determine which individual characteristics predict continued demand for cocaine despite fentanyl adulteration.
This Amazon Mechanical Turk study included self-reported cocaine purchasers (N = 64), who completed self-report questionnaires (demographics, substance use history, depression/posttraumatic stress disorder symptoms, fentanyl knowledge quiz), and the Adulterated Cocaine Purchasing Task.
Results showed (a) that a greater probability of fentanyl adulteration (10%) lowered cocaine demand, but only for intensity (Q₀; amount of cocaine consumed when free; p < .001); (b) no effect on other demand indices (Omax, Pmax, essential value, breakpoint); (c) significantly more zero responders with 10% probability of fentanyl adulteration than 0%, p < .001; and (d) that opioid co-use, depression, age, posttraumatic stress disorder, fentanyl knowledge, and cocaine use severity did not moderate the relationship between fentanyl adulteration and intensity.
Conclusions: Overall, fentanyl adulteration reduced cocaine demand but only for volume preferred at minimal cost, not general motivational drive for use, illustrating the dangerous insensitivity to toxic contamination. The internal validity of the paradigm provides proof-of-concept for this approach to identify individuals at risk from fentanyl-adulterated cocaine.
Related protocols: CTN-0130

Introduction: Despite rising concern about overdoses from fentanyl-adulterated cocaine, research on responses to adulteration among people who use cocaine (PWUC) is limited. We aimed to identify what risk mitigation strategies PWUC would engage in if they suspected fentanyl in their cocaine. Secondarily, we tested whether key individual differences were related to use of risk mitigation strategies.
Methods: A secondary analysis of an online study (CTN Protocol ID: CTN-0130) collected responses from 97 self-reported cocaine purchasers. Participants completed questionnaires on demographics and substance use and reported what they would do if they found out their cocaine might contain fentanyl. Participants selected from a list of behaviors (with a free response option). Responses were coded into a four-level variable: “no change,” “transfer risk,” “harm reduction,” and “abstain.”
Results: About 16.5% endorsed no change in their behavior, 14.4% endorsed transfer risk, 25.8% endorsed harm reduction, and 43.3% endorsed abstain. Of the 10 individual differences tested only cocaine use frequency and previous personal experience of overdose significantly related to selected behaviors. Further analysis showed those with more frequent cocaine use, or prior overdose experience were more likely to use cocaine normally or transfer risk rather than use harm reduction or abstain.
Conclusion: While 83.5% of our sample reported they would attempt to mitigate risk if they suspected fentanyl in their cocaine, participants with more frequent cocaine use or a prior overdose endorsed less use of typical harm reduction or abstention. This highlights the need to direct harm reduction interventions to PWUC to mitigate the fentanyl overdose risks.
Related protocols: CTN-0130