What's in a logo? The Cochrane Collaboration is well-known for its systematic reviews in healthcare. Perhaps less well-known is the story behind The Cochrane Collaboration logo.

Lawrence Sherman, Director of the Jerry Lee Centre for Experimental Criminology at the University of Cambridge, explained how it shows a systematic review of data from seven RCTs comparing one health care treatment with a placebo.

The results concern a short, inexpensive course of a corticosteroid given to women about to give birth too early. They show what would have been known had the available RCTs been reviewed systematically in the early 1980s.

It indicates strongly that corticosteroids reduce the risk of babies dying from the complications of immaturity. (The position of the diamond to the left of the vertical line indicates that the treatment studied is beneficial. Horizontal lines or a diamond to the right of the line would show that the treatment did more harm than good.)

Because a systematic review of these trials was not published until 1989, most obstetricians did not realize that the treatment was so effective. As a consequence, "tens of thousands of premature babies probably suffered and died unnecessarily (and needed more expensive treatment than was necessary)" [Cochrane website].

It raises the worry that there may be other effective interventions in children's services that we use too little or not at all because of a failure to conduct sufficient RCTs in the field or to include them in up-to-date systematic reviews.