Don't use 'Dr Google' to self-diagnose symptoms

Study finds that only one in three online symptom checks proves accurate

19 May 2020 - 06:30 By Claire Keeton
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Online symptom checkers give inaccurate diagnoses a third of the time. Doctors, on the other hand, have the clinical experience to provide proper diagnoses when patients give them a full history.
Online symptom checkers give inaccurate diagnoses a third of the time. Doctors, on the other hand, have the clinical experience to provide proper diagnoses when patients give them a full history.
Image: 123RF/Amikishiyev

Don’t rely on “Dr Google” to diagnose Covid-19 — or just about anything else — if you’re feeling sick. A new study shows that online “symptom checkers” are inaccurate most of the time.

Only about one in three results are accurate, according to Michella Hill from Edith Cowan University in Australia.

“While it may be tempting to use these tools to find out what may be causing your symptoms, most of the time they are unreliable at best and can be dangerous at worst,” said Hill.

Yet many people still turn to Google to get medical advice, self-diagnose symptoms and treat themselves. About 70,000 health-related searches are made on Google every minute, estimates show.

Hill found that the correct diagnosis came up as the first result only 36% of the time. But roughly half the time, an accurate diagnosis was listed in the top three results.

Her research on “the quality of diagnosis and triage advice provided by free online symptom checkers and apps in Australia” was published on Tuesday in the Medical Journal of Australia. It analysed 36 “international mobile and web-based symptom checkers”.

Online tools can provide useful information, said Hill — for example, to alert health services about coronavirus hotspots.

We've all been guilty of being 'cyberchondriacs' and Googling at the first sign of a niggle or headache.
Michella Hill

“We're seeing symptom checkers being used to good effect with the current Covid-19 pandemic. For example, the UK's National Health Services is using these tools to monitor symptoms and potential 'hotspot' locations for this disease on a national basis,” she said.

“We've all been guilty of being 'cyberchondriacs' and Googling at the first sign of a niggle or headache, but the reality is these websites and apps should be viewed very cautiously ... They don't know your medical history or other symptoms.”

They can also provide a false sense of security, she warned. “For people who lack health knowledge, they may think their condition is not serious when it may be.”

The advice on when and where to seek health care was accurate about half the time: appropriate about 60% of the time for emergency and urgent cases, dropping to 30% to 40% for non-emergencies.

Health websites typically provide “triage advice about whether — or how quickly — the user should see a doctor or go to hospital”.

“These sites are not a replacement for going to the doctor,” said Hill.

South African family practitioners said the layperson lacked insight from years of training and clinical experience to interpret symptoms.

Dr Norman Mabasa from the SA Medical Association (Sama) said patients could be exposed to worst-case scenarios or overlook conditions that are contagious or even fatal when turning to the internet for medical advice.

“The internet should never replace the expert help of a doctor, psychologist or psychiatrist, but should aid as a tool to help navigate where to go and how you can get further expert help,” said the SA Depression and Anxiety Group (Sadag).

“Dr Google is only as accurate as those who input the information. Don’t panic straight away when you identify one or two symptoms,” said clinical psychologist Dr Colinda Linde.

“As the old-school GPs say, only when symptoms go on for more than two days, or become suddenly severe, it’s time to consult your doctor.”


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