Table 2.

Domains and Themes Generated From the Coaches’ Interviews and Selected Quotes

Domain	Themes	Selected quotes
Background and experiences with contact sports	• Most coaches played multiple years of tackle football and started when they were young. • Coaches generally felt that starting the sport and learning tackling at a young age helped prepare them for playing football later in life.	• “Like anything else, the sooner you learn the better you are. So, I learned at a young age the proper way to tackle, teamwork, all the good things that come along with … play [ing] football.”
Perceived concussion risks and benefits of youth football	• Coaches were mixed regarding their concerns about the risk for concussion. • Coaches varied in their feelings about subconcussive hits. • Coaches support rules and policies as a way to make football safer. • Coaches reported that youth should begin playing tackle football at a young age. • Coach–parent and coach–athlete communication about football safety is limited.	• “No, I don’t. I don’t think [hits to the head] are a major risk. No. I mean, aside from giving them a concussion, what’s the problem, you know what I mean? Every other sport they’re getting hit in the legs or the arms or the back. What’s the difference with the head?” • “Yes, I think they’re a risk. I think that repetitive hits to the head isn’t a good thing at any magnitude whether it causes a concussion or not.” • “Rules definitely can make football safer. When the facemask first got involved in professional football, you were allowed to tackle by it. And now you can’t do that. You’re going to break somebody’s neck. So, yeah, you could always modify the rules.” • “I think the earlier the better only because their fundamentals are better, especially today. I mean … [my son] played college football. He started playing when he was 6. And I’ve seen a progression in the safety from then, from him being 22 years old.” • “In the beginning of the season I call the parent meeting. I read the warning on the helmets to the parents and to all the players. [I] just remind them—I reiterate what the helmets says on it—and tell them that this is a sport where you can get hurt.”
Experiences with tackling technique training and implementation	• Coaches believed implementation of the tackling techniques was feasible and athletes’ proficiency was high. • Some coaches reported that age affected the athletes’ ability to implement the techniques correctly. • Coaches felt that the CASH + MVP system showed promise for reducing injury, but age-specific drills are needed. • Coaches faced challenges using the MVP. • Coaches preferred in-person training but were mixed on preference between HUF + Hawk and CASH + MVP.	• “I would mark myself a 9 or 10 [on implementing CASH].” • “I think they [the athletes] were successful. On a scale I’d probably say 90 out of 100.”“Natural instinct [of younger kids] is to tackle someone with their head down. So, some kids pick [HUF + Hawk] up fast and some you work with basically the whole season.” • “Having a live person to go through and actually show you the [CASH] drills and show you the excitement of what they’re trying to [teach], it was by far superior.” • “[MVP saves] the live person that you would need to hold the ball to have tackle, but … it’s a negligible impact on the person actually doing the tackling.” • “[the MVP] hurt them because now when you get in the game it’s a person now running.”
Experiences with mouth guard sensor technology	• Coaches claimed the presence of the mouth guard device did not influence their coaching. • Coaches confirmed they did not review the data from the mouth guards.	• “No, I don’t think [the mouth guard sensor] influenced my coaching approach. [ … ] I thought it was good they had them, and they were trying them.” • “[the mouthguard sensor data] uploaded and that was it.”
Personal sources of training related to football safety	• Most coaches viewed their sports league as authority figures. • Coaches differed on the best method for receiving information related to safety.	• “I think that would be helpful because I think when people see stuff, I think everyone learns it easier when they learn it when they’re looking right at it.” • “I mean, in-person’s always better, I guess. But like I said, you can get a lot of information online and you can do it at your own time, you know? Like whenever you have free time.”

Note. HUF = Heads Up Football; CASH = Chest, Arms, Shoulders, and Hands; MVP = Mobile Virtual Player.