In a study designed to minimize flaws found in many earlier studies, a comparison of 52 illicit ecstasy users and 59 matched non-users, aged 18–45 years, revealed little evidence of decreased cognitive performance in ecstasy users, with the exception of poorer strategic self-regulation, possibly reflecting increased impulsivity. This may reflect a pre-existing state, rather than being a consequence of the drug.

To overcome the potential confounding factors in previous studies, potential participants were ruthlessly winnowed. Only those who did not have significant life-time exposure to other illicit drugs or alcohol and did not test positive for drug use at the time of testing were included (a process that terminated in only 52 ecstasy users out of an original 1500). All participants also had to be members of the ‘rave’ subculture.

The researcher points out that regardless of the effects of ecstasy itself, it is dangerous because of the contaminants often found in the pills.