Do hypothetical cannabis surveys predict real-world behavior?

The Marijuana Purchase Task (MPT) is a widely used research tool that asks people how much cannabis they would hypothetically purchase at different prices, providing a measure of relative reinforcing value - essentially, how motivated someone is to use cannabis. Researchers have linked MPT results to important real-world behaviors including use frequency, craving intensity, and cannabis use disorder symptoms. However, a critical question remained: do people's hypothetical responses actually predict what they do when real cannabis and real money are on the line?

This study bridges the gap between theory and practice by comparing participants' hypothetical MPT responses with their actual purchasing behavior in a controlled laboratory setting where they could buy and consume real cannabis. The research validates whether this commonly used assessment tool truly reflects real-world decision-making about cannabis use. Understanding this correspondence is crucial for researchers and clinicians who rely on the MPT to assess cannabis demand, predict problematic use patterns, and evaluate treatment interventions. If hypothetical responses don't match actual behavior, it could undermine the validity of numerous studies and clinical assessments that depend on this measure.