May 26, 2022

Health Information: New Study Looks at Quality of Online Symptom Checkers

From Tech Times:

A new study conducted by researchers at the Harvard Medical School, however, investigated 23 online symptom checkers from the UK, U.S., Poland and the Netherlands. Some of these online symptom checkers are run by well-known brands, such as the Mayo Clinic and WebMD, while some are run by lesser known brands.

The study evaluated 45 patient scenarios on each of the 23 symptom checkers. Out of the total scenarios, 15 needed non-emergency care, 15 required emergency care and the rest may have needed self-care but did not require a medical visit. The cases included 19 uncommon and 26 common diagnoses.

The medical checkers varied in accuracy about the advice given, but they were all quite inaccurate. The researchers discovered that online symptom checkers gave correct advice only about one-third of the time, which means that majority of the primary advice was inaccurate.

Read the Complete Article

The full text of the article the Tech Times article reports on is available here:

Title: “Evaluation of symptom checkers for self diagnosis and triage: audit study”
Source: BMJ 2015;351:h3480

From the Abstract:

Results The 23 symptom checkers provided the correct diagnosis first in 34% (95% confidence interval 31% to 37%) of standardized patient evaluations, listed the correct diagnosis within the top 20 diagnoses given in 58% (55% to 62%) of standardized patient evaluations, and provided the appropriate triage advice in 57% (52% to 61%) of standardized patient evaluations. Triage performance varied by urgency of condition, with appropriate triage advice provided in 80% (95% confidence interval 75% to 86%) of emergent cases, 55% (47% to 63%) of non-emergent cases, and 33% (26% to 40%) of self care cases (P<0.001). Performance on appropriate triage advice across the 23 individual symptom checkers ranged from 33% (95% confidence interval 19% to 48%) to 78% (64% to 91%) of standardized patient evaluations.

Conclusions Symptom checkers had deficits in both triage and diagnosis. Triage advice from symptom checkers is generally risk averse, encouraging users to seek care for conditions where self care is reasonable.


About Gary Price

Gary Price ( is a librarian, writer, consultant, and frequent conference speaker based in the Washington D.C. metro area. Before launching INFOdocket, Price and Shirl Kennedy were the founders and senior editors at ResourceShelf and DocuTicker for 10 years. From 2006-2009 he was Director of Online Information Services at, and is currently a contributing editor at Search Engine Land.