The test was going okay, until I got to this: name four creatures whose names start with the letter “S”. It took me several seconds to get spider and seal. It took me three more hours to remember slug, even though one had appeared on the kitchen floor that morning. Scorpion and sea anemone came much later. Overall, I didn’t do terribly well.

This could have been worrying. The seemingly innocuous question was part of the simple test that, if you believe the tabloid press, “can detect Alzheimer’s in five minutes”. It is not difficult – who is the prime minister, when did the first world war start – but, having completed it, I found my memory wanting. And here’s the thing: I’m not very bothered about it.

The test, recently published in the British Medical Journal, was billed by its authors as a fast and easy way to screen for Alzheimer’s disease, enabling treatment to start early. It sounds good, but there are a number of problems.

The first is the accuracy of the screening method. The 50-question quiz was trialled on patients who had been referred to a clinic after complaining of memory problems. Their test scores were compared with those from controls – usually relatives who had accompanied family members to the clinic.

So, the test is not designed to detect problems in people who might just want “a memory check-up”. It is 92 per cent sensitive for detecting Alzheimer’s disease, but only 82 per cent specific for it. This means that, though it will miss only 8 per cent of people who have Alzheimer’s, it will sometimes detect not Alzheimer’s but another problem. It will sometimes be wrong. And if the test score is low – less than 42/50 – it diagnoses nothing. It merely suggests that further investigation is required.

The researchers also excluded patients with depression from the study. In research terms, this was probably sensible, but the issue of depression and memory still requires attention. At present, and in the “uncontrolled” real world, we are unable to test quickly to see if forgetfulness is down to depression or dementia.

What of other people wanting an “early warning” that they may develop Alzheimer’s? Ordering one’s life affairs is all very laudable, but there are plenty more declines and deaths that come with no warning. Alzheimer’s shouldn’t be the only thing that hastens us to prepare a last will and testament.

As for treatment, I am afraid I think the marketing has been optimistic in terms of what can be achieved. The bottom line is that new medicines do not appear to delay the need for institutional care. For all that, this might be a very useful test, but not one that everyone should take.

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Margaret McCartney is a GP in Glasgow
margaret.mccartney@ft.com

For lively discussion of the latest medical issues go to Margaret McCartney’s blog