Bundles (inform about many findings)

Some tests are “bundles” comprised of many different findings.

Example to work through

Consider a 50-year-old woman with diarrhea, weight loss and anemia, and no history of travel to areas with poor sanitation. On the Add Tests tab there are some bundles, such as a CBC that is often used in routine checkups. Click the word “Bundle” next to the CBC to see its constituent findings. Several different findings in the CBC have significant Usefulness, and as a result the overall Usefulness for the bundle is greater than the Usefulness of any of the individual findings in the bundle. (Registered users can click the images below to jump into the software; some videos may be helpful in navigating from there)

Findings in a bundle (Click the image to jump into the software.)

Although anemia is a finding that can be checked using a CBC, it is ranked as having low diagnostic Usefulness in testing because its result is already known, and it is at the bottom of useful findings in the bundle, which is cut off in the image.

The error associated with ignoring the usefulness of information from other findings in a bundle would be to undervalue tests.

This page is part of a series on the Elements of Diagnosis.