Let me begin by denying having any expertise on medical marijuana. I will also point out that the term “junk science” has been badly overused, and has been used to cast aspersions on evidence that really isn’t junk science at all, including evidence for climate change and evolution. So, for anyone who thinks I am applying this label to the study of which I am about to tell you because I’m a right-wing social conservative, that’s not so. It’s just that I know real junk science when I see it.

I became aware of this study when a friend posted a link to an article from a blog called “Smell the Truth,” whose subtitle says it covers “medical marijuana news.” So, when I read the article from that blog, which put a very positive spin on the findings of the study it described, I thought I should read the original paper to see for myself, which was published in Clinical Gastroenterology and Hepatology – not a journal I routinely read.

The study investigators wanted to know whether smoking marijuana might help patients with Crohn’s disease, which is challenging to control with medical therapy and not infrequently requires surgery to treat complications.

The study, conducted in Israel, took a group of patients with Crohn’s Disease and randomized them to marijuana or placebo. The patients were then followed over the next 10 weeks, and their symptoms were quantified by the Crohn’s Disease Activity Index (CDAI), a standardized research tool used to assess the effect of approaches to treatment.

The authors defined a CDAI score <150 as “complete remission.” I should just point out that the term “complete remission” is misleading, as much of the score depends on symptoms that can wax and wane over a short period of time, while others (four of the eight elements) relate to complications that occur over a longer time. So it is possible to achieve substantial reductions in the CDAI through short-term symptomatic relief without any real change in underlying disease activity.

To call such an effect “complete remission,” then, may give us the wrong impression of what is happening. It would be more accurate to describe the effect as what it is, namely short-term symptomatic relief.

Of course the “Smell the Truth” blog trumpeted the phrase “complete remission” and said the treatment “performed like a champ.”

The number of patients was a mere 21. This is very small – in fact, inexplicably so. The smaller the study, the less likely it is to find significant differences between the treatment and control groups.