INTRODUCTION: People who use anabolic-androgenic steroids (AAS) face health risks from illicit markets and limited tailored harm reduction services. This study aimed to examine whether laboratory testing results from submitted AAS products (ie, compound presence and purity) influence AAS consumers' future behaviours.

METHODS: As part of Wave 3 of a Steroid Testing Trial (2024), community members in Queensland, Australia, submitted AAS samples for laboratory analysis. Using advanced forensic techniques, we tested these samples for compound presence and dosage accuracy. Participants who accessed their results completed a follow-up survey on demographics, AAS use, healthcare access, and response to results. Behaviour change was measured by self-reported modifications to use. Logistic regression examined predictors including perceived helpfulness, confidence to change, quality concerns, prior health effects, and healthcare access barriers.

RESULTS: Of 105 AAS samples analysed, 22% were mislabelled and 50% were underdosed. Most participants who engaged with testing results (N = 117) were men (97.4%), with a mean age of 32, and about half resided in Australia. Nearly all (95.7%) found results helpful, and 45.3% reported behaviour changes, including adjusting dosage, source, or testing compounds before use. Although the logistic regression model was not significant overall, concern about AAS quality predicted behaviour change (odds ratio [OR] = 1.57,  = .026), while perceived helpfulness, confidence, prior health effects, and healthcare barriers were not significant.

CONCLUSIONS: Concern about product quality appears to drive harm reduction behaviours more than perceived helpfulness or confidence. These findings support the value of AAS in drug testing data dissemination that highlights product quality issues.