Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
NFL chief medical officer: Asymptomatic people are not spreading COVID-19 - The Boston Globe
NFL hires Dr. Allen Sills as full-time chief medical officer
Raiders, other NFL teams wear Guardian Caps for head safety, Raiders News
NFL CMO Dr. Allen Sills calls kickoff rule 'stopgap' measure, talks future of playing surfaces, Guardian Caps
Guardian Caps are the latest effort to address CTE, football concussion concerns
NFL Mandates Guardian Caps >> Guardian Sports
NFL Chief Medical Officer Says Guardian Caps Not Coming To Games
NFL on X: NFL CMO Dr. Allen Sills recently joined @nflnetwork to discuss the new Guardian Cap requirement, how they work, and what it means for players in 2022. / X
NFL Chief Medical Officer Dr. Allen Sills talks injury rates on punts, takeaways from 17-game season
Here's how the NFL's concussion protocol really works - The Boston Globe