Three Distinct Risk Profiles Identified Among German Cannabis Users Who Drive High

Three classes emerged: 'Low risk' (48%) with minimal DUIC and risky behaviors; 'DUIC-specific risk' (30%) with high cannabis-impaired driving, peers who also drive high, and low perceived risk, but no other risky behaviors; and 'Global risk' (22%) with multiple risky behaviors and risk factors. Younger age and male gender predicted higher-risk class membership.

Latent Class Analysis of 2023 pre-legalization survey data from 563 German drivers who use cannabis at least monthly. Environmental and individual risk factors and risky traffic behaviors were used as indicators, with sociodemographic covariates.

Not all cannabis users who drive high are the same. The 30% who specifically drive under the influence without other risky behaviors may respond to different interventions (education, peer norms) than the 22% with global risk patterns (who may need broader support). Germany recently raised its legal THC driving threshold, making this segmentation timely.

As more jurisdictions legalize cannabis, determining THC driving limits and enforcement strategies requires understanding who drives high and why. A one-size-fits-all approach may miss the distinct risk profiles this study identified, potentially wasting resources on low-risk users while under-serving high-risk groups.

Pre-legalization survey may not reflect post-legalization behavior. Self-reported driving behavior is subject to social desirability bias. German driving culture and infrastructure may differ from other countries. At-least-monthly cannabis use is a relatively high threshold that may miss occasional users who also drive impaired.