Performance of national COVID-19 ‘symptom checkers’: a comparative case simulation study
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  • Published on:
    Clarifying CDC’s Self-Checker RE: Performance of national COVID-19 ‘symptom checkers’: a comparative case simulation study
    • E. Ivy Oyegun, Epidemiologist/HealthBot Lead CDC
    • Other Contributors:
      • Nicole Maddox, Program Manager
      • William Hampton, Technical Co-Lead
      • Emilia Koumans, Medical Officer/Clinical Team Lead

    Dear Editor,

    Performance of national COVID-19 ‘symptom checkers’: a comparative case simulation study omitted one of the formative aspects of the CDC Coronavirus Symptom Checker (CDC Self-Checker), which is that it regularly undergoes upgrades to content and recommendations in its algorithm. As such, whichever version of the CDC Self-Checker was used in this analysis would have been reflective of vetted CDC guidance at the time it was accessed. The inherent periodic updates of the CDC Self-Checker ensure that it reflects new information and current guidance as those become available.

    Additionally, the omission of an access date indicating when the authors accessed the CDC Self-Checker for their simulation precludes verification of the version used and of the results described in the article. Between this article’s first preprinting in November 30, 2020 and the date of this letter (5/11/21), there have been six revisions to the CDC Self-Checker.

    Finally, the CDC Self-Checker does recommend older adults with established COVID-19 symptoms, such as fever, to seek medical assistance as soon as possible, contrary to the article’s conclusions.

    One of the unique benefits of the CDC Self-Checker is that rather than being a simple Q&A tool, it goes a step further to provide customized recommendations based on personalized and detailed scenarios. The strengths of the CDC Self-Checker provide an innovative and effective complement to health systems wh...

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    Conflict of Interest:
    None declared.