Hundreds of millions of operations are performed every year,

and the risk of death is typically around a half a percent,

to which patients might say things like,

I could just die as easily crossing the road,

making it clear they really don't understand the difference

in magnitude of risk.

One way to communicate risk is by analogy.

For example, just going under anesthetic carries about a one-

and a hundred thousand chance you won't wake up. How much is that? Well, that's about

the same risk as an expert skydive. Okay, but that still may be kind of hard to

wrap your head around.

It's hard to think in terms of small numbers.

Like imagine discussing a 1710,000th of a mile by 22.710, 10,000th of a mile rug.

Like, how big even is that?

We need more digestible units.

Enter the micromort as a unit of comparing and communicating risk to patients.

A micromort is a unit equivalent to a one in a million chance of dying.

One in a million is like the chances of flipping a coin and getting 20 heads or tails in a row,

or a little less than the chances of getting a royal flush.

But the real utility is to help compare different risks to one another using the same metric.

For example, driving 100 miles entails about a 1 million chance of death,

so that's one micromort.

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