Fact/Fiction: Are men over six feet tall more likely to get Covid-19?

How it was told

New information on the nature of the coronavirus has been coming thick and fast in recent months as scientists the world over focus on developing a vaccine.

It has been hard to sort the tall tales from the vital facts but there has been no shortage of coverage on scientific developments as we all eye an end to the pandemic. One recent study looked at the role of height when it comes to transmission of the virus, according to stories reported on July 31 and August 1. Other characteristics have been discussed in the media – for example that children are less likely to contract Covid-19 – but there has been little research into the role of height.

The University of Manchester research was reported by Mirror Online, Mail Online and Express Online, and all three shared the same angle, albeit with some small discrepancies. Mirror Online’s report had the most general headline. It read: “People who are over 6ft tall are twice as likely to catch coronavirus, study claims”.

As for Mail Online, their headline focused on men. They opted for: “Does being tall raise the risk of getting Covid-19? Men over 6ft are TWICE as likely to get infected, study claims”. And Express Online went for the more clickbait-friendly: “Coronavirus update: Men this height are twice as likely to get infected, study claims”.

Metro, The Daily Telegraph and The Scotsman also reported on the study. But do these stories stand tall or are they short on fact?

Facts. Checked

This study does not prove any causal link between being over 6ft tall and catching Covid-19, and there is also doubt over the level of association between the two.

The claim came from a survey of 1,000 adults of working age in the UK and a similar survey in the US, with the study yet to be peer-reviewed. One of the problems with the headlines mentioned above is that the results showed a difference between the results from both sides of the survey.

In the UK there did appear to be an association that showed that men over 6ft tall saw increased rates of transmission, but this was not true in the US side of the survey. This fact alone saw two of the news outlets update their stories and change their headlines.

If you click on the Mirror Online story, the headline now reads “British men over 6ft more likely to report having had coronavirus” while the Express Online’s story is under the header: “Coronavirus update: Study suggests men over 6ft could be more likely to get infected”. Both also feature a correction stating that the association linking height and Covid-19 transmission was found only in the one British survey and no causal link was proven. It is largely down to the work of Big Issue Changemaker Full Fact, which investigated the study, that these stories have now been updated.

There are other issues too. The survey covered quite a broad number of factors but it only asked whether the person was over 6ft, making it difficult to measure the results against other heights.

One of the study’s authors, Professor Evan Kontopantelis, reacted to the stories on Twitter, pouring cold water on the height theory and suggesting that height was a proxy for other information, such as occupation. He said: “Being tall is extremely unlikely to be a risk factor. Height is confounded by other characteristics. The key message is aerosol transmission looks likely.”

Being tall is extremely unlikely to be a risk factor. Height is confounded by other characteristics. The key message is aerosol transmission looks likely. https://t.co/P9djyYOPj2

— Evan Kontopantelis (@dataevan) July 30, 2020

He also told Full Fact that the “key message of the study was that downward droplet transmission may be less important than aerosol transmission” after researchers ruled out the hypothesis that tall men are protected to some degree from droplets expelled from noses and mouths that would fall to the ground.

But this study did not measure airborne transmission so it can’t prove any relation to transmission and height. More study is needed, of course, but for now these stories can be cut down to size.

Image: Miles Cole