Anti-depressants do not work, chorused British newspaper headlines this week. The truth is quite different. The research in question showed that new-generation drugs, such as Prozac and Seroxat, relieve depression very well – but so do dummy pills.

The study, led by Irving Kirsch at the University of Hull, is the latest testament to the power of the placebo. Analysing the drug companies’ own clinical trial data, the researchers found that four widely prescribed drugs improved patients’ score on the standard clinical test for depression by 9.6 points, while placebo pills gave a remarkable 7.8-point improvement.