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Commentary: Instructions on self-administering COVID-19 tests should not be so bewildering

Perhaps if the instructions were written from the user’s point of view, it might be more intuitive – a lesson applicable to many areas of our lives, says the Financial Times’ Tim Harford.

Commentary:  Instructions on self-administering COVID-19 tests should not be so bewildering

Man using a home test kit for coronavirus while standing in his bathroom. (Photo: iStock)

LONDON: I recently had the doubtful pleasure of self-administering a mail-order COVID-19 test.

It was a process that required simultaneously mastering the test itself, packing up the sample, and registering the procedure online.

This administrative, logistical and medical triathlon would have been challenging at any time, much like applying for a driving licence while assembling an Ikea chair, parts of which I had to insert into various orifices.

Still, the bewildering instructions did not help. They were supplied in two not-quite-identical versions for an anxiety-inducing game of spot-the-difference.

Mysterious components went unexplained.

On a third instruction sheet was a stern admonition to write down the parcel-tracking number, which could have referred to any of a dozen serial numbers, since the whole kit was festooned with more barcodes than a branch of Tesco.


Why couldn’t these people design a less mind-boggling set of instructions? The answer, my friends, is “the curse of knowledge”.

The phrase, coined by three behavioural economists, describes the difficulty a well-informed person has in fully appreciating the depth of someone else’s ignorance.

A veteran of parcel delivery knows exactly what a parcel-tracking number looks like. It is so obvious that she will use the term without a second thought, much as you or I would use the word “it”.

Of course, the word “it” can itself be devilishly ambiguous. There’s a PG Wodehouse story in which Bertie Wooster warns a bedroom intruder that his valet will soon be bringing him morning tea: “He will approach the bed. He will place it on the table.”

The intruder is perplexed as to why the valet would place the bed on the table. In Wodehouse’s tale this is comical, because in context “it” is not remotely ambiguous.

But when an expert is trying to explain something to a novice, there is no context. “It” could mean anything, as could “parcel-tracking number”.


We humans are egocentric creatures. We can’t help but see things from our own perspective. In his book The Sense of Style, Steven Pinker offers a pithy example of this egocentrism at work.

He receives dozens of coursework assignments with file names such as Pinker.doc. For his students, it makes sense to give such a file name to an essay for Professor Pinker, but it betrays a striking failure to put themselves in his shoes.

The most famous study of this problem is by a graduate student in psychology, Elizabeth Newton. She put experimental subjects into pairs and asked one person to tap out a well-known song on the table.

Using only their knuckles, they would perform “Baa Baa Black Sheep” or “Raindrops Keep Falling on My Head”. The other person had to guess the song. The listeners found this extremely hard, succeeding fewer than three times out of 100.

But the tappers thought the task would be much easier and that listeners would guess the song about half the time. This is because Newton’s tappers could hear the tune in their heads as they tapped out the rhythm. They simply could not imagine what it felt like to hear only the tapping.


In 2005, the psychologist Justin Kruger and his colleagues studied this egocentrism problem in the context of written communication.

Participants were asked to write two sentences, one of which was straightforward while the other was dripping with sarcasm.

Then they were asked to estimate how difficult other people would find it to spot the sarcasm.

They believed the recipients would get it right almost every time. This was far too optimistic: 20 per cent of sentences were misinterpreted. In the context of a work email, that failure rate is easily enough to ruin your day.

The curse of knowledge isn’t new. The catastrophic charge of the Light Brigade during the Crimean War in 1854 was essentially the result of ambiguous orders being misinterpreted.

In a world where so much information is now conveyed in writing — email, text, social media — it is worth paying attention to how to prevent such confusion.

Anyone who has assembled a Lego set can attest that, with enough care, it is possible to provide clear instructions even for complex tasks.

The most straightforward solution is to check how the message is being interpreted and then to check again. Alas, it is the nature of the curse of knowledge that we often fail to appreciate how necessary such checking is.

A man wearing a face mask browses his smartphone lining up with residents to receive their vaccine at a vaccination point at the Central Business District in Beijing. (Photo: AP/Andy Wong)

It is one subject that we journalists do understand, which is why this commentary has been read by numerous editors before reaching you. If the final result is confusing, I apologise. But you should have seen the first draft.

Package designers need a second and third opinion too. I suspect that if the testing company had spent more time watching people like me trying to follow their instructions, they would soon find improvements.

My wife agrees. “They just need to hire an idiot and watch him try to figure out the test,” she observed. Then she looked thoughtfully at me.

Unlike Bertie Wooster’s “it”, there was no misunderstanding which idiot she had in mind.

Source: Financial Times/sl


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