The nomogram epidemic: resurgence of a medical relic.

The obsolete calculators known as nomograms have become epidemic in recent medical literature. The frequency of articles in PubMed retrieved with this search term nearly doubled between 1990 to 1999 and 2000 to 2007. Popular in medicine from about 1925 to 1975, a nomogram is a crude graphical means for solving an equation by placing a straightedge across several scales. Today, most reported nomograms are inconsistent with both established definitions and half a century of clinical use. The need for nomograms disappeared with the advent of personal computing. Instead of constructing nomograms, authors should develop software, such as prediction models, that can either be downloaded to personal digital assistants or be used on the Internet. Modern computing features both accuracy and speed; nomograms offer only the latter.