Luckily, the trial is actually a rather neat spoof paper, written for educational purposes to highlight bad practices in the design and writing up of clinical trials. It's accompanied by a serious piece which analyzes these problems. They're both open access so you can take a look.
The sham study is ostensibly a trial of a new antidepressant, "placeboxetine", compared to an older drug for depression - but it was really written by one of the Editors of the journal via "Common shortcomings in manuscripts submitted to the Indian Journal of Psychiatry were collated into a single manuscript". These shortcomings are certainly not limited to Indian papers.
The problems included:
- No placebo group. This is extremely common in trials comparing two drugs, so it's "accepted practice", but it's still a bad thing.
- The "placeboxetine" was given at a higher dose, relative to its dose range, than the comparison drug but they don't say why.
- Side effects are reported but they don't explain how these were assessed. If you specifically ask about them you find a lot more than if you rely on patients to spontaneously complain.
- Subtle, but important, issues with the statistics, such as reliance on t-tests over more appropriate methods.
- The trial had some unusual features for a depression trial - with no explanation. Most patients were males in their 20s, while the norm is for about 65% females and an average age in the 40s; very few people dropped out; very few people who were screened were excluded, whereas most trials exclude loads of people for all kinds of reasons.
- The effectiveness of both drugs was remarkably high (75% cure rate over 6 weeks - better than any treatment, drug or therapy, would be expected to show.) Yet they don't mention this.
- It was badly written. The title in particular was far too long and clumsy.
- It turns out that the trial was sponsored by the fictional pharmaceutical company, and was probably conducted to help get placeboxetine sold in India - but we only find this out in the small print at the end.
- Hot pink and white is not a good color scheme for your graphs, or for anything except marshmallows. (I may have added this myself.)
Andrade C (2011). A 6-week, multicentre, randomized controlled clinical trial to evaluate the safety and efficacy of placeboxetine hydrochloride in the treatment of major depressive disorder in an Indian setting. Indian journal of psychiatry, 53 (1), 69-72 PMID: 21431013
Andrade C (2011). Placeboxetine for major depressive disorder: Researcher, author, reader, and reviewer perspectives on randomized controlled trials. Indian journal of psychiatry, 53 (1), 73-6 PMID: 21431014
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