Addictions, Drug & Alcohol Institute
Addictions, Drug & Alcohol Institute > Cannabis Education & Research Program (CERP) > Cannabis Projects

Cannabis Projects

Current projects (as of January 2025)

CannTalk: A Brief Intervention for Discussing Cannabis with Clients Experiencing Psychosis

CannTalk Discussion Guide

October 2023 – February 2025
Status: Dissemination of findings (preparation of paper for publication)

CERP finalized a pilot feasibility study of a brief clinical intervention to reduce cannabis related harms among people experiencing psychosis, in collaboration with Dr. Denise Walker from the UW School of Social Work. Grounded in Motivational Interviewing (MI), the CannTalk intervention is designed to equip Coordinated Specialty Care teams and Behavioral Health Clinicians with skills to communicate more effectively about cannabis and guide clients towards reducing or quitting their cannabis use. 

Funded by the Washington State Legislature through ESSB 5187 (2023) and by the Washington State Dedicated Cannabis Fund for research at the University of Washington. 

Investigators

Resources

Assessing Engagement in Cannabis Policy: A Baseline Survey of Elected Officials Washington 

October 2023 – June 2025
Status: Data collection complete, analysis plan under development

This project aims to evaluate how elected officials are engaged in cannabis policy in Washington and better understand their perspectives on regulating cannabis in the state. 

Funded by the Washington State Legislature through ESSB 5187 (2023) 

Investigators

A Matter of Equity: People Living with Psychosis are Disproportionately Affected by Cannabis Adverse Events

October 2024 – June 2025
Status: Data analysis

This project analyzes data from the International Cannabis Policy Study collected between 2020 and 2023. Its aims are to compare the prevalence of cannabis-related adverse effects among people who used cannabis in the last 12 months, according to their mental health diagnosis (no mental health diagnosis, Psychotic disorder diagnosis, Any other mental health diagnosis but psychotic disorder).

Funded by the Washington State Legislature through ESSB 5187 (2023) and by the Washington State Dedicated Cannabis Fund for research at the University of Washington. 

Investigators

Cannabis Adverse Events in Clinical Practice: An Assessment of WA Clinicians’ Practices, Knowledge and Needs

October 2024 – June 2025
Status: Recruitment and data collection

Little is known about clinician knowledge, beliefs, and clinical practices in cases involving cannabis-related AEs. Understanding clinician beliefs and behaviors related cannabis adverse events can inform future clinician education and training. It can also map opportunities for implementing clinical interventions that can prevent cannabis AE recurrence and severity by encouraging patients to quitting/decreasing their cannabis consumption or to adopt safer use behaviors.  

Accordingly, this project will conduct a needs assessment study exploring knowledge, beliefs, clinical practices, interest on intervening on cannabis AE and personal and institutional barriers for addressing cannabis AEs among health care providers in Washington State. 

Funded by the Washington State Legislature through ESSB 5187 (2023) and by the Washington State Dedicated Cannabis Fund for research at the University of Washington. 

Investigators

Reporting THC Content in Cannabis Products in Legal Markets: An international Multidisciplinary Delphi Consensus Study 

Status: Data collection

In countries where cannabis products are legal, the THC content on licensed cannabis products is inconsistently reported (e.g., % percentage or concentration, milligrams). This project aim to establish guidelines on how to report the amount of Delta-9-Tetrahydrocannabinol (THC) consistently and accurately across all cannabis products. To achieve this goal, the project will utilize a Delphi methodology with a multidisciplinary and international expert to achieve consensus on how to report THC content for consumers (e.g., product labelling and packaging) across all cannabis products (e.g., medical/non-medical, administered via distinct modes).

Steering Committee members

Cannabis Adverse Events among Medicaid Recipients in WA State 

July 2024 – June 2025
Status: Request for data access and IRB approvals

With cannabis legalization in WA State has come an increase in cannabis use prevalence, daily use, and THC concentration of available products. These changes have been linked to corresponding health care utilization due to cannabis-related adverse outcomes in Colorado and Canada. These outcomes range from acute events such as panic attacks, cannabis-induced psychosis, vomiting and cardiac events to conditions that typically develop over time, such as cannabis hyperemesis syndrome and cannabis use disorder. Little is known about health care utilization due to cannabis-related adverse outcomes in WA State, the type of events seen most frequently, and how and if they are being recorded in medical records and claims.  

This project will use statewide Medicaid claims data to describe cannabis-related adverse outcomes among Medicaid patients in primary care, hospitals, and emergency departments across the state. Descriptive analyses will (aim 1) identify the prevalence of specific types of cannabis-related events, (aim 2) who is most affected (age, race/ethnicity, gender, county, and other diagnoses), and (aim 3) the healthcare settings most commonly responding to these events.

Funded by the Washington State Dedicated Cannabis Fund for research at the University of Washington. 

Investigators

Cannabis Consumer Patterns, Adverse Events, and Cannabis Risk Beliefs: A Latent Profile Analysis in WA State 

July 2024 – June 2025
Status: Paper submitted and under review

Cannabis use has changed with changing availability of different product types. This cross-sectional study used data from Washington State (WA) residents between 16-65 years old collected between 2019 and 2022 as part of the International Cannabis Policy Study to identify user profiles through Latent Profile Analysis. 

Six groups were described that differed by frequency of use of different cannabis products/modes, ranging from the lowest use group that averaged weekly use of primarily flower to a group characterized by daily use of concentrates. Contrasting with previous studies that indicate that adverse events increase with THC levels and frequency of use, this group reported significantly fewer adverse events than the next most frequent users who used a greater variety of product types. These findings may be influenced by transitions between groups, which is not captured in this cross-sectional study. The four groups with most frequent use across multiple modes, were all significantly more likely to self-identify as “addicted” than the lowest use, primarily flower, group. There were few differences in risk beliefs between groups. 

Funded by the Washington State Dedicated Cannabis Fund for research at the University of Washington. 

Investigators

Completed Projects (alphabetical)