1. MTP Marijuana Treatment Project The Multi-site Study of the Effectiveness of Brief Treatment for Cannabis Dependence A Cooperative Agreement funded by SAMHSA-CSAT

2. yAre brief treatments more effective than deferred treatment (referral to a waiting list control group)? yDoes a 9 session treatment produce better outcomes than a 2 session treatment? yDo these treatments vary in effectiveness in diverse population groups in relation to gender, ethnicity, and employment status? Primary Research Questions

3. Rationale for a Multi-site Trial yMarijuana is the most commonly abused illicit substance in the U.S. yLarge numbers of chronic users have developed cannabis dependence yPrevious small-scale clinical trials have demonstrated the efficacy of brief and extended treatments yFurther research is needed to test the robustness of effect and its generalizability to broad populations

4. MTP Collaborating Sites zSponsoring Agency ySubstance Abuse and Mental Health Services Administration/ Center for Substance Abuse Treatment zCoordinating Center yUniversity of Connecticut, School of Medicine, Farmington, CT xYale University, New Haven, CT zClinical Research Units yUniversity of Washington, Seattle, WA yUniversity of Connecticut, School of Medicine, Farmington, CT yThe Village, Inc., Miami, FL

5. Experimental Groups zBrief Treatment Group (N=146) y2 sessions of Motivational Enhancement Therapy yDelivered over a 5-week period zExtended Treatment Group (N=156) y9 sessions: 2 of Motivational Enhancement Therapy, 5 of Cognitive Behavioral Therapy, and 2 of Clinical Case Management yDelivered over a 12-week period zDelayed Treatment Control Group (N=148) yTreatment initiation scheduled 4 months after date of study enrollment yChoice of brief or extended treatment at end of delay period

6. Study Design

7. Overview of the Cognitive Study zPurpose yTo evaluate the effects of short-term (4-months) abstinence on recovery of cognitive functioning zDesign yCognitive assessment battery administered to DTC volunteers at beginning and end of treatment yTreatment responders (abstainers) will be compared with clients who continue to use MJ

8. Assessment Procedures & Variables zMTP Screening Questionnaire yDemographics yCurrent alcohol and drug use yLifetime dependence history yMedical and psychiatric history zStructured Clinical Interview for DSM-IV yDSM-IV criteria for alcohol and drug abuse and marijuana dependence

9. zTime Line Follow-Back Interview yWeekly summary data for frequency of marijuana, alcohol and other drug use for ‘past 90 days’ ySummary of quantity of marijuana, alcohol, cigarette use for ‘past 90 days' yHazardous use of marijuana for ‘past 90 days’ zAddiction Severity Index yLifetime & current alcohol and drug history yMedical history yEmployment and support status yLegal history yPsychiatric history Assessment Procedures & Variables

10. zSelf Report Questionnaires yBeck Depression Inventory ySelf Efficacy Questionnaire yReasons for Quitting yMarijuana Problem Scale yReadiness to Change Questionnaire yCoping Strategies Scales yAmbivalence Measure yState-Trait Anxiety Inventory zUrinalysis y10 Psychoactive Substances

11. Inclusion/Exclusion Criteria zMeets DSM-IV Diagnosis for Cannabis Dependence zHas smoked cannabis on at least 40 of the last 90 days zDoes not meet DSM-IV dependence criteria for other drugs or alcohol zIs not involved in concurrent therapy or 12-step meetings zDoes not have a medical or psychiatric diagnosis that would interfere with treatment

12. zIs within 60 miles of clinic zIs able to name one person to serve as a locator zHas legal status that allows involvement in the protocol zIs not subject to mandatory urine screens zIs at least 18 years old zHas the ability to speak and understand English Inclusion/Exclusion Criteria, cont.

13. Demographic Characteristics of MTP Participants (N=450)

14. Demographic Characteristics of MTP Participants, cont. (N=450)

15. Marijuana Use Characteristics at Baseline (N=450)

16. Marijuana Dependence Symptoms Endorsed at Baseline (N=450)

17. Marijuana Dependence Symptoms Endorsed at Baseline, cont. (N=450)

18. Marijuana Related Problems Endorsed at Baseline (N=450)

19. Marijuana Related Problems Endorsed at Baseline, cont. (N=450)

20. Lifetime Treatment History Reported at Baseline (N=450)

21. Number of Days of Marijuana Use in the Past 90 Days - Baseline (N=450) Mean = 80.0 SD = 14.6

22. Number of Joints Smoked Per Day in the Past 90 Days - Baseline (N=450) Mean = 2.9 SD = 2.3

23. Number of Hours High Per Day in the Past 90 Days - Baseline (N=450) Mean = 6.6 SD = 4.6

24. Number of Marijuana Dependence Symptoms Endorsed in the Past 90 Days - Baseline (N=450) Mean = 5.6 SD = 1.3

25. Number of Marijuana Related Problems Endorsed on the MPS - Baseline (N=450) Mean = 9.6 SD.= 3.6

26. Marijuana Use Within 1 Hour Prior to Driving in the Past 90 Days - Baseline (N=450)

27. Marijuana Use Within One Hour Prior to Working on a Paid Job in the Past 90 Days - Baseline (N=373)

28. MTP Treatment Attendance (N=450)

29. MTP Follow-up Rates

30. Participants Lost to 4-month Follow-up

31. Participants Lost to 4-month Follow-up, cont.

32. Treatment by Time (Baseline, Week 1- Week 16) % of days smoked marijuana per week (N=398)

33. Treatment by Time (BL, Wk1, Wk5, Wk12, Wk16) % of days smoked marijuana per week (N=398)

34. Intention to Treat Analysis (N=450) Treatment by Time (BL, Wk1, Wk5, Wk12, Wk16) % of days smoked marijuana per week

35. Treatment by Time (Baseline, 4-Month Follow-up) SCID Dependence Symptoms (N=398)

36. Treatment by Time (Baseline, 4-Month Follow-up) Marijuana Problem Scale (N=398)

37. Products and Anticipated Accomplishments of MTP zNew findings on the clinical characteristics of chronic marijuana users zNew findings on the effectiveness of brief treatments of marijuana dependence zNew assessment instruments zNew treatment interventions zTreatment manuals for therapists and primary care practitioners zEdited volume of scholarly papers

38. Research Implications zDevelopment and validation of screening tests and referral procedures zEvaluation of primary care applications of MET brief intervention zEvaluation of brief and extended treatments in CD/behavioral health provider network outpatient settings in terms of xImplementation xEffectiveness xCost-effectiveness

39. Unfinished Business zCost effectiveness study zTraining package covering: yAssessment yDiagnosis yTherapist skills ySystem issues zLong-term outcome evaluation