By Walt Hickey

Welcome to the Numlock Sunday edition. Each week, I'll sit down with a writer behind one of the stories covered in a previous weekday edition for a casual conversation about the story they wrote.

This week, I spoke to Drs. Kathleen Bachynski and Zachary Binney, the researchers behind a groundbreaking new study about CTE. Here's what I wrote about it:

In 2017, researchers published the findings that 110 of 111 NFL players who had donated their brain tissue to a study of chronic traumatic encephalopathy (CTE) received that posthumous diagnosis. That figure, while shocking, raised clear questions of selection bias. A new paper published in Neurology untangles that question. Chiefly, even if selection bias was extremely high, at least 10 percent of NFL retirees would show signs of CTE on autopsy. Even if players with CTE were 461 times more likely to donate their brain to the study than those without CTE, a minimum of 20 percent of retirees would show signs of CTE, and if it w…