Masks, you may not have worn them before 2020 but now we’re all at it. With the rise of the Omicron variant countries have scrambled to reintroduce public health policies, among them mask wearing. Health officials and scientists agree that masks help reduce the incidence of covid19 infections – but by how much is still debated. Several newspapers recently reported that masks could cut Covid-19 infections by 53%, we look at how they came to this number and whether we should be believe it. (Image: Leon Neal/Getty Images)

Vaccines are the best way to stop deaths and serious cases related to covid19, this is an irrefutable fact. However, recent ONS data seems to show that vaccinated people had a higher all cause death rate than unvaccinated people. Why is this data misleading? Here’s a clue: it’s to do with a quirky statistical phenomenon called Simpsons Paradox. (Image: The Simpsons / TCFFC )

Nowadays if you are an academic and who needs some participants for a study you go online, but over the summer academic studies were inundated with participants who all happened to be teenage girls ... we explore how one TikTok can tip the balance of data gathering. Presenter: Tim Harford Producer: Chris Flynn (Image: TikTok logo is displayed on a smartphone screen/Getty/NurPhoto/contributor)

A French minister told people to eat fewer croissants at this year’s COP26 summit, after the menu said the carbon cost of the pastry was higher than that of a bacon roll, even if it was made without butter. Tim Harford investigates whether this claim could be true, and how the effect of food on climate change can be measured. (Image: Continental breakfast with coffee and croissants: Getty/Cris Cantón)

When Professor Martin Schweinsberg found that he was consistently reaching different conclusions to his peers, even with the same data, he wondered if he was incompetent. So he set up an experiment. What he found out emphasises the importance of the analyst, but calls into question the level of trust we can put into research. Features an excerpt from TED Talks (Image: Getty/erhui1979)