Also known as punch-drunk syndrome, CTE is a progressive, degenerative disease of the brain associated with repeated concussions.
An independent research project at Boston University has identified its presence in the brains of 90 of 94 former National Football League (NFL) players it examined. With the science still in its infancy, the key questions now become who conducts this research and what are their objectives?
In 2012, the NFL granted the National Institutes of Health US$30 million ($41.2m) for a research project as an "unrestricted gift". And yet as a devastating 91-page Congressional report concluded in May, top NFL officials waged a campaign to steer the project towards employing its own in-house researchers rather than independent experts.
The report concluded: "In this instance, our investigation has shown that while the NFL had been publicly proclaiming its role as funder and accelerator of important research, it was privately attempting to influence that research."
In July last year, World Rugby and the New Zealand Rugby Union presented the findings of a three-year study, funded by World Rugby and conducted by the Auckland University of Technology. Its findings, that more research was needed, were unremarkable.
Yet using the Official Information Act, the Herald last month revealed the extent of the discord and disagreement between AUT's lead researcher, Patria Hume, and World Rugby officials. Hume emailed a colleague saying: "They [World and NZ Rugby] just do not want us to say there is any issue at all" regarding cognitive impairment. World Rugby and the NZRU both deny that they attempted to influence the report.
In Britain, Jeremy Wilson last month outlined how the Football Association failed to publish a study it commissioned with the Professional Footballers' Association to investigate the prevalence of dementia among former footballers.
There are many, many good people involved in sports administration who have athletes' best interests at heart. Yet, as these examples demonstrate, the temptation to soft-peddle or bury the risks can be overwhelming. The only safeguard can be that all future research is fully independent, peer-reviewed and kept at arm's length from the tentacles of the sports governing bodies.
Anything else is open to abuse.
Read more from our concussions series at nzherald.co.nz