Before you open this issue, you hopefully noticed the new format of the journal? Some of the changes are obvious, such as the less cluttered cover, and the reduction in shaded boxes in the abstracts. But other changes are more subtle, such as the separation and reformatting of the “Study design” and “Study question.” We hope you like the changes, but as we are always looking to improve, we are also keen to hear other suggestions for improvement.

Dan Hughes recently triggered a useful discussion on the EBHC email list by asking about "the issue of applying evidence to a single patient in the clinic or at the coal face." Several good suggestions were made, but Rod Jackson capped the discussion with a quote from Aristotle: “None of the arts (ie, science) theorise about individual cases. Medicine, for instance, does not theorise about what will help to cure Socrates or Callias, but only about what will help to cure any or all of a given class of patients. This alone is business: individual cases are so infinitely various that no systematic knowledge of them is possible.” (Aristotle. Rhetoric. book I, chapter 2: 1356b.) Those wanting an in-depth look at what we have learned since Aristotle should look at Peter Rothwell's excellent book Treating individuals: from randomised trials to personalised medicine (Elsevier, 2007). The book includes some wonderful data on individualising decisions such as carotid endarterectomy that show the promise of personal risk assessments.

However, not all attempts at individualising therapy are helpful. In this issue, we report on a randomised trial that compared standard warfarin dosing with a genotype-guided programme. The tailoring did not improve the outcome of out-of-range international normalised ratios. While personalised medicine is intrinsically appealing, if off-the-shelf works as well and costs less, we should stick to that. But I am sure we will see more attempts at improving therapeutic targeting.