Wednesday 6 May 2020

Have 300,000 smokers quit because of COVID-19?

On Monday, I mentioned the claim from Action on Smoking and Health that 300,000 smokers have quit as a result of coronavirus fears. I said that it seemed unlikely that such a figure could be confidently derived from a survey of 1,000 people.

Simon Clark has got hold of the YouGov survey and my suspicions have been confirmed. As he explains...

Of the 1,004 people polled, 56% (562) were never smokers; 31% (307) used to smoke but have given up; 9% (90) smoke every day; and 4% (40) smoke but not every day.

In other words, only 13% of the sample (130) were current smokers, significantly less than the national smoking rate.

The most important group however were the 310 people (or 307 according to the data) who used to smoke because it's from their responses that ASH extrapolated the headline figure of 300,000 smokers who have allegedly been driven to quit 'over Covid-19 fears'.

I'm no mathematician and I've been struggling to get my head round the figures, but with a bit of outside help this is how I think they did it.

First, let's round up the figures so the sample size is 1,000 people of whom 130 were smokers, and 310 ex-smokers.

Two per cent of the 310 ex-smokers cited concerns about Covid-19 being the reason they quit smoking in the last four months.

That's six people, or 0.6% of the 1,000 people polled.

The adult population of the UK is approximately 50 million and 0.6% of 50 million is ... 300,000.
The bad news therefore is that the headline-grabbing figure of 300k appears to be based on the responses of just SIX (6) smokers who have quit in the last four months.

ASH's maths are roughly correct, but it is a massive stretch to convert six people into 300,000 people. It is very risky to form any conclusions based on a tiny proportion of people responding to a survey because, as I have said before..

...there are always going to be some respondents to surveys who don't read the question, don't understand the question, don't tick the right box or are having a laugh.

In total, the survey found 28 people who claimed to have quit in the last four months, of whom six said that they had quit 'solely or partly due to COVID-19 (e.g. because of; the health risk, not going to the shops to buy tobacco, no social smoking)' - ie. not solely because of 'coronavirus fears'.

Extrapolated across the whole country, this suggests that 1,350,000 people have quit smoking this year. Does that sound remotely plausible in a country which has 6.5 million smokers? At best, there is going to be a huge relapse rate.

As with most ASH research, the factoid about 300,000 Covid quitters deserves to go in the bin.

No comments: