Letter to the Editor
1 UCLA Medical Center, Emergency Medicine Center, Los Angeles, CA 90024-1744
Many of the bedside assessments that physicians perform as part of the history and physical examination may be viewed as "tests" and, as such, may be subjected to analysis of their diagnostic discrimination.1 To determine the clinical utility of a test we need to determine: 1) precisely how it is to be done, 2) the range of normal values, and 3) its value to predict a clinical abnormality. The latter is done by Bayesian analysis, ie, when we suspect a clinical condition how often does a patient who tests positive have the condition and how often does a patient who tests negative not have the condition.




