Methodology: 3/5
Usefulness: 2/5

Trubiano JA, et al. JAMA Intern Med. 2020 May 1;180(5):745-752. 

Question and Methods: Prospective derivation and subsequent retrospective validation of a clinical decision rule for the detection of patients at low risk for true penicillin allergy.
Findings: The PEN-FAST rule has an NPV of 96.3% for predicting those at low risk for true penicillin allergy.
Limitation: The external validation was done retrospectively and the study did not provide any safety data on the consequences of false-negative results.

Interpretation: The PEN-FAST rule has limited use in the ED as most patients may be too unwell to undergo the therapeutic penicillin challenge.

By: Dr. Tina Chiang

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  • Hans Rosenberg

    Dr. Rosenberg is an emergency physician at the Ottawa Hospital, assistant professor at the University of Ottawa, and Director of the Digital Scholarship and Knowledge Dissemination Program.