Restricted accessResearch articleFirst published online 2026
A Brief Motivational Enhancement Intervention to Promote COVID-19 Testing and Vaccination Among People Who Inject Drugs: A Randomized Controlled Trial of Connect2Test
To examine the incremental effectiveness and costs of a motivational enhancement intervention, Connect2Test, embedded in syringe service programs (SSPs) on COVID-19 testing and vaccination uptake among people who inject drugs (PWID).
Design
Two-arm randomized controlled trial.
Setting
SSPs in Oregon.
Sample
PWID (n = 349) receiving services at SSPs. Participants were 18 years or older (M = 43.9), English-speaking, and mostly male (60%), White (64%), non-Hispanic (87%), and had low-income.
Intervention
Participants were randomized to contingency management (CM; ie, $10 gift card) only (n = 172) or to CM + Connect2Test (n = 177).
Measures
COVID-19 testing and vaccination (outcomes) and costs associated to Connect2Test training, staff delivery, materials, and facilities.
Analysis: Used multilevel logistic regression to compare rates of COVID-19 testing and vaccination administered on the same day of the intervention and anytime during a 9-month follow-up period. Estimated incremental costs of CM + Connect2Test relative to CM-only using the ingredients method and a societal perspective.
Results
Relative to CM-only, the CM + Connect2Test group had 296% greater odds of receiving a vaccination during the 9-month follow-up period (3% vs 11%; OR = 3.96, 95%; CI = 1.43-10.94). No group differences were found for same-day vaccination or testing, or future testing. The estimated cost of a vaccine with Connect2Test was $575.
Conclusions
A brief motivational intervention delivered by SSP staff increased COVID-19 vaccination among PWID.
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