PA PSRS Patient Saf Advis 2005 Sep;2(3):12.
PT—How Many Meanings?

In his book Medical Abbreviations (, Neil Davis points out that there are no standards for many abbreviations used in healthcare. He notes that, because many people use their own variations of abbreviations, they are not always understood and may be misinterpreted. This can cause delays in initiating therapy, perpetuate serious errors, waste time obtaining order clarification, and in-crease the resources needed to educate healthcare provid-ers. As an example, in the following set of orders, the ab-breviation “PT” is used five different times with four different meanings: percussion therapy, physical therapy, patient, and prothrombin time. 

Davis calls for a controlled vocabulary, similar to what is used in aviation and the military, where accurate communication is so critical. All pilots and air traffic controllers use a standard nomenclature when repeating back the letters in a word: they say “alpha,” “bravo,” and “charlie” (for A, B, and C), not “apple,” “beef,” or “candy.” They also say “two-seven-zero,” not “270,” which can sound like “two seventeen.” The idea of a controlled vocabulary is behind Joint Commission’s and ISMP’s efforts to standardize abbreviations that should never be used in medicine. While the Joint Commission has already established a minimum requirement with its list of abbreviations that should never be used, we hope that healthcare organizations will take note of our full list of abbreviations( that have, at one time or another, led to medication errors.

What does “PT” mean? Imagine you’re a new student reading this order set! 

Editor’s Note: This article first appeared in the publication ISMP Medication Safety Alert!, Volume 10, Issue 8, April 21, 2005. It is reprinted here with permission of ISMP.


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