Internet self-diagnosing often gives you the wrong diagnosis

Looking for health advice is one of the most common reason people search the web. Many websites provide health information and some even offer self-diagnosis using a symptom checker. After entering all of the symptoms the website suggests a possible diagnosis and advises to take some home remedies or see a doctor. A study recently mentioned on this blog showed that Wikipedia had errors in 9 out of 10 articles on different medical conditions.

Another recent study by Harvard researchers examined the accuracy of the sites that offer self-diagnosis. Not surprisingly, this study also found that the online programs are often wrong. The results were published in the British Medical Journal.

The lead author Ateev Mehrotra, commented that “These tools may be useful in patients who are trying to decide whether they should get to a doctor quickly, but in many cases, users should be cautious and not take the information they receive from online symptom checkers as gospel.”

Some of these symptom checkers were developed by prestigious institutions, including Harvard and other medical schools, major hospital groups, insurance companies, and some government agencies (including the United Kingdom’s National Health Service).

The researchers presented 45 hypothetical cases (including headaches) to test 23 different symptom checkers. Only 34% listed the correct diagnosis first and the correct diagnosis was in the top three possibilities in 51% of cases.

Dr. Mehrotra said that “It’s not nearly as important for a patient with fever, headache, stiff neck, and confusion to know whether they have meningitis or encephalitis as it is for them to know that they should get to an ER quickly.”

Of the 23 symptom checkers 58% provided correct advice and in more serious conditions, it correctly recommended emergency room visit in 80 percent of cases.

To complicate matters, the checkers with the most accurate diagnoses (Isabel, iTriage, Mayo Clinic, and Symcat) were not the ones that were best at recommending the appropriate level of care (Healthychildren.org, Steps2Care, and Symptify).

The researchers compared the online symptom checkers with a live telephone triage nurse offered by many insurance companies. The accuracy of live nurses is between 61% and 69%, so these are more accurate accurate, but also leave a lot of room for improvement. Hopefully, these online programs will continue to evolve, but at this point, you should not rely on them.