"If it's bad, I'd rather not know"

This chapter is about the fear underneath the other reasons, and I'd like to treat it with respect. Fear of serious illness is one of the most reasonable fears a person can have. If part of you is staying away from the doctor because you're frightened of what you might hear, that part of you is trying to protect you.

My question is whether it succeeds.

The protection is supposed to work like this. If the news is bad, not hearing it keeps you out of the bad world a little longer. But that only holds if the bad world is equally bad whenever you enter it. For most serious conditions that isn't so. It matters a great deal whether the news arrives early or late.

Cancer Research UK publishes survival figures by the stage at which cancers are diagnosed, using NHS data for England from 2016 to 2020. For bowel cancer, about 91 per cent of people diagnosed at the earliest stage survive five years or more. For those diagnosed at the latest stage, the figure is about 11 per cent. For breast cancer in women, the figures are 98 per cent at the earliest stage and 27 per cent at the most advanced.

I should be careful about what those numbers do and don't show, because they're easy to misuse. They don't mean that any one person who waits six months moves from the first group to the last. Cancers differ in how fast they grow, and some are found late however prompt the person was. Part of the gap is an artefact of measurement, since a cancer found earlier has a head start on the five-year clock. A large review of the evidence on delay, by Neal and colleagues, looked at 209 studies. It found them so varied in quality and method that firm overall conclusions weren't possible. What the reviewers could say was that for several cancers, including breast, bowel, head and neck, testicular and melanoma, more of the studies found that shorter times to diagnosis went with better outcomes. They concluded that it's reasonable to assume that faster diagnosis benefits patients, though the benefit varies from one cancer to another.

There's firmer evidence on delay once a cancer has been found. Timothy Hanna and colleagues pooled 34 studies covering more than 1.2 million patients, and looked at what happened when treatment was delayed. For surgery, each four-week delay was associated with a 6 to 8 per cent increase in the risk of death. That's about the wait for treatment after diagnosis, which isn't the same as the wait before seeing a doctor. But it suggests that time matters, at the scale of weeks.

I'm not going to press these figures further, and I won't repeat them. This isn't a book that works by frightening you. If fear were enough to get you to the doctor, you'd have gone in March. I give them once because they answer the question this chapter asked. "I'd rather not know" assumes that knowing later costs the same as knowing now, and it doesn't. If the news is bad, its size isn't fixed. How big it turns out to be depends partly on when you hear it, and you have some control over that.

There's a gentler point as well. Most of what people fear isn't cancer at all. The tooth that twinges needs a filling, which is a dull twenty minutes. If you leave it three more years it may need a root canal, or to come out. High blood pressure that's found at a health check can be treated with a daily tablet. If it goes unfound, it can lead to a stroke. For the ordinary run of conditions the pattern is the same. When a problem is caught early, the treatment is usually smaller and the outlook better. The NHS page on dental check-ups puts it plainly. Leaving problems untreated could make them more difficult to treat in the future.

So the frightened part of you has it backwards. It treats the doctor as the source of the bad world. For most conditions, though, seeing the doctor early is how that world is kept small.