Journals demand a lot of their readers. Each week we present a bundle of disparate articles with the tacit challenge to “make sense of that.” It's no wonder that journal articles don't play much part in helping doctors to change their practices—but they can, at their best, help create a climate for change, increase understanding, prompt thought, and provoke debate.

Research studies in particular are submitted and published in no particular order, and something we publish this week might contradict something we published two months ago—or, probably even worse—might be on the same subject but pursue a completely different line of inquiry. …