In the UK, for example, the average man and woman are 178cm and 164cm tall respectively, and earn around £34,000 and £25,000 – and we might even know people who fit these two characteristics. But the search rapidly gets harder as we add more ‘typical’ characteristics, those who perhaps also drink the average amount per week, spend the average amount on food and so on. You’d need hundreds of people to find at least one matching all these characteristics, and ever more as you try to pin down the ultimate ‘average person’, who is so unlikely they probably don’t exist. This is a major challenge to ‘personalised’ medicine, as many drugs have been shown to work on average, but then fail with many patients – none of whom is ever just average.
