Table 4. Categories identified in interviews with middle school athletes, parents, and staff related to the category of “communication”.

Category	Example quotes
Pathways and content of communication between MS sport groups Athletes (n = 19/19) Parents (n = 20/20) Staff (n = 18/18)	Coach discussions with athletes about fair play “The coaches might say be cautious and respectful of others. And try not to be super aggressive” (Athlete #12022) “trying to teach them in addition to [their sport], how to be a good citizen, those kinds of things.” (Parent #11019) Coach discussions (or lack there of) with parents “Depends on the coach. I wouldn’t say they communicate with us a lot, it’s mainly around sort of the logistics—of getting to the right place at the right time.” (Parent #11056) “…there were a couple times I had face to face conversations with the coach. And it was at the beginning, just introducing myself and you know, letting her know that I was excited about <<Athlete’s Name>> being on the team.” (Parent #21023) “We don’t really have, I guess, more personal conversations with parents unless they initiate that.” (Staff/Coach #23001) “I have not talked with school staff. Really haven’t talked with parents a whole lot. Again, mostly just the athletes about things on the court and in practice.” (Staff/Coach #43003) Discussions of injury, particularly concussion “If there’s like an injury I try to send a notification to an individual parent-”(Staff/Coach #33003) “We just said said person had a concussion, was going to be out to be out for a while and then we moved on.” (Athlete# 12056) “You always hear like somebody got a concussion that’s why they can’t play or—But not that much.” (Athlete #22040) “I guess, we usually start by just—it usually comes up with an incident. So, we kind of describe what happened in the incident. Honestly, we don’t really talk a whole lot about prevention of it because when we’re talking about it, it’s kind of already happened. And so, the conversation is more, what we should do moving forward. And then maybe when the athlete starts playing again, we start talking about things to do on the court to avoid reinjury.” (Staff/Coach #43003) “It does happen. Well, like I said, we have our preseason meeting. And those topics are addressed and discussed… seldom do we get any questions about this. So it’s hard to kind of answer anything if they’re not inquiring. During the season, if it does happen, then obviously we’re handling it case by case. Postseason, we really don’t talk much about it so, just get ready for the next season. That’s kind of what we’re doing.” (Staff/Coach #53003) “We have an interest meeting for the kids at school and you’ll have a parent meeting usually after the first week of practice and after that you really don’t have much of, it’s really not conversation time. It’s more worried about—- Play and practice and learning how to play the game. So, that can be an issue. I think we try to impart in our players, because once an injury happens we talk about it.” (Staff/Coach #23003) “I remember talking about concussion and I didn’t really feel qualified to talk to a kid about it” (Parent #21006). “I mean I think it’s a…it’s a conversation you need to have or you can have it in the proper setting. You know, it’s not just one of those ‘Hey, I’m going to grab this out of left field and start talking about concussions. . .’ So, whether…there may not be a good opportunity that presents itself to talk about it. I mean obviously, if you’re in a sports situation you’re going to have to play football…or watching your kids playing football, you can bring it up. But if you’re out having dinner with a bunch of people or something, I don’t think, you know, concussions is going to come up a lot.” (Staff/Coach #53005) “I certainly wasn’t going out and saying, ‘Hey, my child had a concussion and here’s what he or she struggled with, has your kid ever had that?’ But it’s amazing how many people just start talking” (Parent #11051) “So it kind of wasn’t—it was talked about I think with one player because he actually had a concussion, but with the other players and like during the plays it wasn’t really talked about much it was just more of like, what can we do to provide … support” (Parent #41003) Parent interaction with one another “With the parents it’s usually like at the games, the ones who come to the games are sitting by each other and cheering together, talking together. At the end of the season we generally do some sort of end of season party in an altogether different setting than a game that is celebratory.” (Parent #11022) “We [[the parents]] all want to know each other and talk about the game and compliment their kids on how they’re playing and what not and other feedback or nice things you’ll mention about their son type of thing. So, yeah, we’re always happy to see each other at the games and you show up and it’s “Hey, there’s parent x and parent y.” We sit together and just kind of talk.” (Parent #21006)
Mode Athletes (n = 8/19) Parents (n = 18/20) Staff (n = 16/18)	Use of school athletics website, apps, or email “We have like a big communication system—called 8 to 18 that we all kind of like communicate through and emails, like we have a weekly email that kind of like settles out where all the fields are being used and all that and then like on the field pretty much.” (Staff/Coach #33003) “We have an App that we go through. Like a management software, it’s called Team Snap. And I mostly just send emails through that and it has the schedule and the volunteer slots on it. Oh, that’s how I communicate with parents on the team and players too.” (Staff/Coach #43001) “Most coaches here, do one of two things. If they are a bigger team—like a non-cut sport. Like track, or cross country, they have easily 60 athletes. They use Remind. Our smaller teams use email contact for the most part.” (Staff/Coach #73003) “But then what the coach does is…he sends out a weekly email. Each week he’ll send out ‘Hey, this coming week we have this game here,’ ‘don’t forget about this thing”‘ or whatever. And then he’s like ‘email me any time if you have questions or whatever.’ That’s the best way.” (Parent #11019) “The 8 to 18… I’m getting used to it. You know, it’s different because it’s, you have to like work to get to it…” (Parent #21040) Role of a team parent “And if you don’t have a parent who’s going to monitor and manage that it doesn’t always work well. If you have a parent who steps up to be sort of an administrative person who can stay on top of that, the coach can reach out to you, for example, that works better.” (Parent #31015) “Yeah, we have a team parent. And the team parent usually relays other messages to the other parents.” (Staff/Coach #13003). Communicating through the athletes “But a lot of times our information is going through the athletes every day at practice. So we are hoping that they transfer that information to their parents.” (Staff/Coach #73003) Preseason parents meeting “We do have a parent meeting in the beginning so that sort of everybody gets the same general athletic information. And then sport specific information.” (Staff/Coach #73003) “We have our preseason meeting. . .We answer questions, Q&A.” (Staff/Coach #53003)
Barriers Staff (n = 15/18) Not a category for athletes and parents	Athletes and parents not being receptive to concussion prevention and response messaging “Like when people aren’t totally receptive—Like, you know the kind of, oh it’s just like, you just suck it up or something—if someone’s more like that it’s really hard to talk.” (Staff/Coach #33003) “I think sometimes people are just like…we have this mentality of just like ‘man up’ or ‘just push through it’ kind of. And so….I don’t think people fully understand the full effects. Again, like the long-term effects of having concussions. So, I think sometimes they just brushed it off. Like, ‘that’s not really like a big deal.’” (Staff/Coach #73010) “Yeah, and it’s also that they’re in middle school and they’re stubborn and sometimes they just don’t realize it and they think they’re invincible and it drives you nuts. I mean I’ve heard stories, [inaudible] my stories of kids who just are ‘Oh, I’m fine.’ ‘You’re really not.’ And they just think they can go through it and it’s ‘You need to tell me immediately when it happens because that’s the best thing for you. Don’t make it worse than it is.’” (Staff/Coach #23003) “I think it’s kind of that balance between like, not wanting to freak out the parent, but also wanting the parent to take it seriously. You also, you know, run into parents who will say, you know, ‘my child is fine’ and you really disagree with them. So that just gets kind of gets uncomfortable.” (Staff/Coach #43003). Parents not trusting expertise of school staff “You’re looking at the <BLINDED> school system that has a very high rate of highly educated parents that may not want to hear anything less than a physician. You have another population that a nurse might do it. You have a population that’s like “Yeah, I don’t want either one of you.” (Parent #34001) “Maybe with a parent after a kid was injured. And like they’d be accusatory looking at me, like, why didn’t you stop this from happening? …you know, questioning my coaching. Rather than, you know, why the kid got hurt. Obviously, I can tell you why their kid got hurt, but if a parent was upset with the way it happened and tried to maybe spite me for something like that, would be uncomfortable.” (Staff/Coach #43004) Length of season “with the middle school sports season being so short, if they are experiencing a concussion in the middle, they are possibly out for the rest of the season” (Staff/Coach #44001). Communication issues “If a concussion happens at home, on vacation, etc. I may not find about it for a while. Because if the parent doesn’t let us know we won’t know. Sometimes later the child will be having symptoms and the parent might let the coach know and then they can let me know.” (Staff/Coach #14001) Barriers related to athlete’s homelife “We do have some English language barriers, parents for whom English is not their first language. It’s typically Spanish. We have a Burmese girl this year on our team too. Her mother is from Burma so there is a language barrier. (Staff/Coach #23033) “I can’t tell you how many different countries, how many different languages. So, sometimes culture will play a role in what they’re willing to do specifically with the medical community.” (Staff/Coach #44001) “Some kids don’t even have a parent, right? They’re foster care.” (Staff/Coach #34001)