For my next trick...

PAXIL was a blockbuster. It was introduced by its inventors, GlaxoSmithKline (GSK), in 1992, as an antidepressant. By the early 2000s it was earning the firm nearly $2 billion a year. It was being prescribed to millions of children and teenagers on the basis of a trial, called Study 329, which suggested it was a good treatment for depressed youngsters. But when British regulators took a second look at Study 329, in 2003, they concluded that it had been misleadingly presented. Not only did Paxil do little to help youngsters with depression, it often made things worse—to the extent of making some who took it suicidal. In 2012 the American authorities imposed the biggest fine in the history of the pharmaceutical industry, $3 billion, on GSK for misreporting data on a variety of drugs, of which Paxil was one.

Since then, Study 329 has become one of the best-known examples of a piece of academic sleight-of-hand called “outcome switching”. This is a procedure in which the questions that a scientific study was set up to answer are swapped part way through for a different lot. Study 329 set out to measure the impact of Paxil on eight different variables, all based around how participants scored on a variety of depression tests. None showed that it was any better than a placebo sugar pill, but the researchers who wrote the paper came up with 19 new measures. Most of those showed no benefit either, but four did. In the paper, those four were presented as if they had been the main measures all along.