#although actually casper's research was part of former NHL players' suit

[girderednerve]

"C.T.E. is the subject of furious controversy. Some of the debate has been stoked by researchers affiliated with the sports industry, who argue that we still don’t know for sure that head blows in football, hockey, soccer, or rugby can lead, decades later, to the dramatic mood problems, the personality changes, and the cognitive deterioration associated with C.T.E. These experts maintain that, before we rethink our relationship with these sports, we need scientific inquiries that meet highly rigorous standards—including longitudinal studies that would take fifty to seventy years or more to complete. In the meantime, millions of children and high-school, college, and pro athletes would continue butting heads on the field.

[Stephen Casper, a historian of science and medicine,] believes that the science was convincing enough long ago. 'The scientific literature has been pointing basically in the same direction since the eighteen-nineties,' he told me. 'Every generation has been doing more or less the same kind of studies, and every generation has been finding more or less the same kinds of effects.' His work suggests that, even as scientific inquiry continues, we know enough to intervene now, and have known it for decades.

Casper’s historical work, begun in 2015, painted a clear picture: for at least seven decades, if not longer, many prominent physicians and sports organizations, including the N.C.A.A., had been well aware that concussions from a variety of sports could cause cumulative, crippling brain damage. 'People who wanted to know could know,' Casper told me. 'People who wanted to warn could warn.'

The standards of scientific rigor that C.T.E. skeptics invoke were widely adopted only in the late nineties. According to Casper and other critics, their main effect in the controversy over concussions in sports has been to emphasize uncertainties and obfuscate what’s known."