Precision and Recall in Surgical Research

PRECISION AND RECALL

Imagine there is a serial killer on the loose following a frenzied rampage.

You are the law administrator responsible and have to act. What would be your strategy?

There could be many answers to this broad question but perhaps one common theme would be to widen the search as much as possible and round up suspects, thus diminish the chance of a slip away.

Now several months later imagine you are the judge presiding over the case and a defendant is brought before you. What would be your strategy?

Again there are many ways a court case could proceed but at the end of the day there should be substantial evidence that the person before you is guilty and this should be clearly demonstrated. There should be little or no chance that an innocent is convicted, this being a fundamental maxim in legal jurisprudence called Blackstone’s principle.

You can see two distinct values at play in each of these circumstances, and they seem to dovetail well.
In the first the killer should not escape, no matter what.
In the second an innocent should not suffer, no matter what.
Both designed with one aim, which is to ensure fair and effective justice.

These two strategies have been enshrined in these complimentary arms. They have been consciously and purposely flamed and forged in the furnace of civilisational evolution. These are recall and precision respectively. 

There is a sweet spot corresponding to the narrow intersection of the Venn circles of power and accuracy in the strike of a ball for instance. There is a similar threading of the finest of needles required when you have to decide what to eat in an all-you-can eat buffet. This is also how a diagnostic test is deemed trustworthy; good enough to pick up signal (true diagnosis) but not bad enough to pick up too much noise (false diagnosis). The bathwater goes, the baby stays.

Interestingly this could be seen as a special case of a more fundamental strategy made almost by every living creature at every level, namely ‘trade-off’. Thomas Sowell, one of the great contemporary American economists famously said that there are no solutions but only trade-offs.

What do you think would be an example of the fine balance of precision and recall that you perform day in and out at home, work or otherwise? 

Odysseus, the king of Ithaca, suffered the wrath of both Scylla and Charybdis, two terrifying sea monsters residing on either side of the Strait of Messina before redeeming himself and his ship to survive. Literally the prototype Odyssey.

In the medical syndrome called ‘DIC’, a nightmare condition for intensivist doctors to manage, the dichotomous problem of excessive bleeding and excessive clotting is often referred to the ‘Scylla of haemorrhage’ and the ‘Charybdis of thrombosis’. One can only sympathise with both the patient and the medical team as they navigate a very tortuous path ahead in the fog as treating one will inevitably worsen the other, and vice versa.