A leading neuroscientist has criticised football's approach to researching the link between heading and dementia for "putting all their eggs in one basket".
Dr Magdalena Ietswaart featured in Sunday's BBC documentary on dementia and was the co-author of a 2016 study that revealed the short-term effects heading a ball has on the brain.
Ietswaart's team conducted their study at the University of Stirling and the technology they used to test their experiments was funded by the National Institute of Health Research.
Having invited research groups to apply for new funding in March, the Football Association and the Professional Footballers' Association (PFA) had been hoping to reveal a project in time for Sunday's programme but an announcement is still a few weeks away.
However, it is understood a UK-based research group has been chosen, a six-figure sum allocated and the question the study will try to answer agreed, which is – are cases of dementia more common among ex-professional footballers than in the general population?
Dr Ietswaart has welcomed the decision to fund research but is concerned the study will not find the answers people really need.
Speaking to Press Association Sport, Dr Ietswaart said: "The truth is we do not know enough about the link between heading and brain damage, if there is a link, because the research has not been done yet.
"We need research not just to find out whether there is a link but also what is the link. We need to understand it because we are talking about the really messy science of correlation.
"The Football Association is asking the question the public has asked but by only asking that question – by putting all their eggs in one basket – there is a risk we will still not know what the dangers of heading the ball are for the 250 million players worldwide who head the ball many times, often from a young age."
Dr Ietswaart explained that unless we know what heading the ball does to the brain, we can never make informed decisions about what age it is safe to start heading, how often we should do it, whether that is the same age for boys and girls and whether other risk factors should be taken into account.
"I hope more scientists will do this research – it is a real challenge to develop sensitive, robust, informative ways to tell what is going on, to help understanding move forward," she said.
"But if the scientific community knows there is funding for solid independent research – because the sporting bodies really want to know, not just say they do – then the neuroscience community will answer."
Dr Ietswaart contrasts British football's research efforts to those now undertaken by the National Football League in the United States, where a large fund is available to multiple research projects, what she describes as a "space prize" approach.