"Better safe than sorry"

This is the argument that defends the habit when everything else has been conceded. The searching may frighten you and cost you sleep, but you'd rather be frightened than miss something. Searching feels to you like a kind of vigilance.

I agree with the principle, and I don't think searching satisfies it. Being safe, with a symptom, means getting it in front of someone who can assess it, at the right speed. Searching isn't a step towards that. It comes before that step or takes its place, and it can lead you wrong in two ways.

The first is the one this book has mostly described. You end up terrified of something unlikely. You may then go to the doctor in a panic, or you may be too scared to go at all. While you stay away you only suspect it, and the doctor might confirm it.

The second is the opposite, and it gets less attention. Sometimes people search in order to talk themselves out of going. They read until they find a harmless explanation that fits, and then they decide that's what it is, and the lump or the bleeding or the cough goes unexamined for months. A search can't rule the worst in or out, as chapter 4 said. If you use one to reassure yourself about a symptom the NHS says to get looked at, that isn't safe either.

So whichever way the search goes, fear or false comfort, it hasn't made you safer. Only the assessment does that.

And the assessment is closer than the search makes it feel. For a worrying symptom you have a pharmacist, who can be asked without an appointment. There's 111, by phone or online, which exists to tell you how quickly something needs seeing and by whom. And there's your GP surgery. Each of them can do what you wanted from the search in the first place. They take your particular symptom, in your particular body, and tell you whether it needs attention.

One finding from the symptom checker study is useful here. Semigran's team found that the checkers' advice about what to do was generally cautious. They tended to send people for care when looking after themselves would have been reasonable. That's a fault in a symptom checker. It's also a reminder that the careful, cautious route is already there and doesn't require an hour on a forum. If you want to be safe rather than sorry, ask someone qualified, early, and do what they say.