JMIR Publications

ABSTRACT

Background:

The McIsaac criteria are a validated scoring system used to determine the likelihood of an acute sore throat being caused by Group A Streptococcus (GAS) in order to stratify patients who need strep testing

Objective:

We aim to compare McIsaac criteria obtained during face-to-face (f2f) and non-f2f encounters.

Methods:

This retrospective study compared the percentage of positive GAS tests by McIsaac score for scores calculated during nurse protocol phone encounters, eVisits (electronic visit) and in person f2f clinic visits.

Results:

There was no difference in percentages of positive strep tests between encounter types for any of the McIsaac scores. There were significantly more phone and eVisit encounters with any missing score components compared to f2f visits. For individual score components there were significantly less eVisits missing fever and cough information compared to phone encounters and f2f encounters. F2f encounters were significantly less likely to be missing descriptions of tonsils and lymphadenopathy compared to phone and eVisit encounters. McIsaac scores of 4 had positive GAS rate of 55-68% across encounter types. For encounters not missing any score components and a McIsaac score of 0 there were no positive GAS tests.

Conclusions:

McIsaac scores of 4 collected during non-f2f care could be used to consider empiric treatment for GAS without testing if significant barriers to testing exist such as during the COVID-19 pandemic or significant geographic barriers. McIsaac scores of 0 in encounters without any missing score components can be used to exclude need for GAS testing.