The quality of diagnosis and triage advice provided by free online symptom checkers and apps in Australia

In reply: Ada’s symptom checker was identified using the selection process described in our article.1 For the search term “symptom”, Ada was the second listed program; for “symptom checker” and “health symptom diagnosis”, Ada appeared third, but it did not appear for “medical diagnosis” and “cough fever headache” search terms. A number of other European‐based symptom checkers were identified via our search strategy; therefore, a bias towards CE (Conformité Européene)‐marked symptom checkers appears unlikely.

Three websites and four Apple Store and two Google Play smartphone applications (apps) (including Ada) were similarly excluded, as users are required to register an account. Such sites request specific data to establish personal profiles which would have created inconsistencies with the standardised vignettes. Due to word count limits, this specific component of our exclusion criteria was not explicitly stated in our manuscript. The objective of this research was to review symptom checkers through the application of vignettes of varying urgencies. Therefore, symptom checkers that required time to establish accounts and verify registration via email were deemed unsuitable for testing urgent or emergent situations.

We are gratified by the interest from Ada and hope our research continues to inspire ongoing development.