Vital signs: the dangers of cyberchondria

I have learned a new word this week: cyberchondria. It basically means giving yourself the willies by self-diagnosing on the internet. It’s something that comes up a lot in my life, as more of my patients are doing it. I’m frequently asked about it in interviews, and I make TV shows with associated websites that positively encourage it.

Londoners are particularly fond of using the internet to diagnose, usually because of time constraints, but there are right and wrong ways of going about it.

Writer Malcolm Gladwell reckons it takes 10,000 hours to make an expert. A junior doctor’s first year probably covers about 4,000 hours and consists mainly of learning just one thing: who is really sick and who isn’t. That can be very difficult indeed, and there is still a long way to go after that. So it stands to reason that an amateur attempt at armchair diagnosis may often be unsuccessful. It’s very hard to remain emotionally detached when diagnosing oneself, and to apply cool logic when sifting through possible diseases. The temptation to apply the worst you come across is strangely powerful.

Scientists at Microsoft analysed the internet behaviour of a million surfers around the world to discover how it is giving many of us rare but imaginary diseases. One of the main reasons is that common diseases don’t feature much in writings — they are dull. Exciting things such as brain tumours do, and so are frequently present in searches for headaches, even though they are rare.

One of the most useful pieces of advice I was given in medicine is to apply a little rule called Occam’s Razor. It can be interpreted in many different ways but I like to explain it simply as: “Common things are common”. A more colourful version is: “If you hear hooves, think horses not zebras”.

This gem has proved itself right time and again and reminds you that you are more likely to have something that everyone gets rather than a rarity.

Our innate hypochondria will make our internet diagnoses wrong 99 per cent of the time because we will likely have a common problem. Even the uncommon is likely only to be an uncommon manifestation of a common disease, rather than a common manifestation of an uncommon disease.

I’m a fan of patients looking things up. I think the internet has made patients more interested in their own health and more inquisitive about things they can do to help themselves. It also keeps us doctors on our toes, otherwise our patients know more than us.

The one big stumbling block is the quality of the information available. Medical websites have improved over the years but as a general rule of thumb, if a web address ends in .edu or .org, the content is less likely to be tosh. A .com suffix usually indicates business sponsorship, so I urge more scepticism. I generally steer well clear of one-man bands.

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