Determinants of ecstasy use and harm reduction strategies: informing evidence based intervention development


This PhD. thesis reports eight studies into the determinants of ecstasy use behaviours. Although all prior quantitative studies into ecstasy use determinants have examined the generic behavioural category ‘using ecstasy’, these studies may not be able to inform the development of interventions aiming to prevent ecstasy use or to promote cessation. The studies reported in this thesis indicate that the key determinants of ‘using ecstasy’ are not also the key determinants of ‘trying out ecstasy’ and ‘ceasing ecstasy use’. Furthermore, ecstasy use cessation usually seems to be prompted by life style changes (e.g. job/work, relationships, losing interest in the dance scene), rather than by fear of ecstasy’s health effects. This means that health promotion efforts would do better to adopt a harm reduction approach, rather than to focus on abstinence. The current thesis reports the studies on which these conclusions are based, and the first study into the determinants of a harm reduction strategy.

If you want, you can also buy this phd thesis in hardcover (€ 24.00) or paperback ($ 9.00), or a booklet with the introduction, discussion, references, and summary ($ 6.50) at

Proposition (stelling): 

Research aiming to inform ecstasy use interventions should not study the behaviour “using ecstasy”.

Many ecstasy users cease use circumstantially when they move on to another life phase.

Ecstasy use interventions should aim at promoting harm reduction, rather than abstinence.

Meta-analyses are an incarnation of extreme specialisation: they draw very powerful conclusions, but on very narrow issues.

Quantitative research without qualitative research is blind; qualitative research without quantitative research is powerless.

There are very rarely good reasons to dichotomise a variable, and there is a very good reason to not dichotomise variables.

Reporting effect sizes is more informative than reporting p-values.

Journal editors’ and reviewers’ tendency to prefer the familiar and the traditional, and their suspicion of the unknown impede innovation and thereby scientific progress.

Legalising drugs would save lives, increase the quality of life of many people, and decrease criminality.

A ‘scientific debate’ is a contradictio in terminis.

“You must not think me necessarily foolish because I am facetious, nor will I consider you necessarily wise because you are grave.” - Sydney Smith

Front cover thumbnail: 
Time & date of defense: 
Friday, 19 December, 2008 14:00