"But it might happen"

Every worry carries a small, fair point inside it. It might happen. Managers do deliver bad news, and so do boilers and scans. Nobody can promise you otherwise, and I won't try.

The useful question is how often. Worrying rarely asks that, because it deals in "could" and leaves "how likely" alone. While you're in a round, a one in a hundred chance and a one in two chance feel about the same.

In 2020 Lucas LaFreniere and Michelle Newman published a study that did the counting. They took 29 university students whose worrying was severe enough to meet the criteria for generalised anxiety disorder. For ten days the students wrote down their worries whenever a phone prompt asked them to. They were told to record only specific worries that could be tested, the kind that would clearly either come true or not within a month. Then for thirty days they tracked what happened.

About 91 per cent of the worries didn't come true. Each student had recorded 34 separate worries on average, so there were plenty of them. The most common score for one person was 100 per cent, which means that for seven of the 29, not a single thing they'd worried about happened. The worst score anyone got was 53 per cent untrue. So even the unluckiest person in the study was wrong more often than right.

The study also looked at the worries that did come true. The students rated about 30 per cent of those as turning out better than they'd expected, about 44 per cent as bad as expected, and about 26 per cent as worse.

I'd be misleading you if I made this sound bigger than it is. It's a small study of 29 people, nearly all of them young women at one American university. The students judged their own outcomes. Only worries that could be settled within a month were counted, which leaves out the slow ones, such as "what if I never meet anyone" or "what if my pension isn't enough". I don't know of a larger study that has repeated it with other kinds of people. But it's the only careful count of this sort I could find, and I think it agrees with what most people find when they check their own record.

And people almost never check it. When a worry doesn't come true, nothing happens to mark it. The chat on Thursday turns out to be about Leeds, and within an hour you've forgotten you were ever frightened. Nobody adds it to a tally. The one time in ten that the fear was right is a different matter, because it was painful and you remember it vividly for years afterwards. "I knew it. I had a feeling about that." So your memory holds a short list of hits and no list at all of misses, and from that record worrying looks like a reliable guide.

Suppose a racing tipster were wrong nine times in ten. You'd stop buying his tips within a month, provided you could see his record. Your worrying has never had to publish one.

You might fairly say that one in ten isn't nothing, and that some of those could be serious. I agree. If a boiler engineer told you there was a one in ten chance of a gas leak, you wouldn't shrug. But look at what you'd do. You'd have it fixed, that afternoon. A real risk of one in ten calls for a piece of preparation, which is a job with an end. It doesn't call for forty rounds of thinking about it. The likelihood tells you whether a concern deserves some action. Nothing about it tells you to rehearse.

There was one more finding in that study. The students who saw the highest share of their worries fail to come true improved the most over the course of it. The authors take that to mean that watching your own predictions fail, in writing, is part of what helps. I can't promise you the same effect, but it costs almost nothing to try.

So turn the three predictions from chapter 1 into a running log. It can be a page in a notebook or a note on your phone. When you catch a worry, write it as a prediction with a date, in one line. Once a week, go back and mark each one that has come due. Put a tick if it happened and a cross if it didn't, and add a word on whether it was as bad as you'd thought. Don't try to argue yourself out of anything. For now you're only keeping score, which is more than your worrying has ever done.