It’s an old dilemma in youth sports, one that has frequently pitted player against trainer, coach against doctor, parent against school. but Heather Campbell doesn’t have to rely on gut feeling and teen self-evaluations, or even her substantial experience in the field. in this case, the trainer simply got out her smart phone, logged on to the web-based testing platform to which Casa Grande subscribes, and scrolled through the results of a cognitive test the player had taken that day.

“Everything was at baseline, and he was good to go,” Campbell said.

Casa Grande is one of the few high schools in the area to have a certified athletic trainer on staff, and is believed to be the only one in Sonoma County to use the Concussion Vital Signs system. It’s one of the latest tools in the treatment of head trauma, an injury that in recent years has been linked to everything from Alzheimer’s and dementia to depression, Parkinson’s and Lou Gehrig’s Disease when occurring repeatedly.

For $375 a year, Casa has access to virtually unlimited pre- and post-injury testing. Here’s how it works, in a nutshell: Under Campbell’s supervision, every Gaucho playing a contact sport — football, soccer, basketball and wrestling are mandatory; volleyball, softball and baseball are optional — logs on to the Concussion Vital Signs website and takes a series of tests that measure memory, concentration and problem solving in various ways.

In one segment, the program randomly generates 15 words and flashes them on the screen, one by one; the participant then has to identify those words nested among 15 new words. another section records how many times an athlete can tap the Space bar with his or her right index finger in 10 seconds. in another, the participant must quickly compare one geometric object with two others. It might be, for example, a red square up high, and a red circle and a blue square down below, and the program will direct the participant to match either the color or the shape. Responses are measured by the millisecond.

The entire test takes 45 minutes to an hour, and it is undeniably tedious. Campbell had one football player fall asleep while tapping.

But the effort breeds a valuable result. once Campbell has baseline results for each athlete, she can test someone after an injury and get an objective read on how impaired they are.

Campbell, who also teaches PE and sports medicine at Casa Grande, receives no extra pay for administering the concussion program, though she has spent many hours setting it up.

She emphasizes that she is not qualified to diagnose concussions. that must be done by a physician. but her testing is an important tool at the doctor’s disposal — both in diagnosing and in deciding when the symptoms have subsided enough to allow re-entry. Campbell will usually retest 24 hours after the initial injury, and then a couple days later, and if the post-injury measurements are more than 5 percent off the baseline, that student probably isn’t going to see the field.

“It gives us one more thing to say, ‘this is where you are. this is what needs to happen,’” Campbell said.

During any game at Casa Grande, it is Campbell or her cohort, retired paramedic Chuck Gant, who decides when a player — visiting team included — is at risk to continue. She will shine a light at the athlete’s pupils and ask a few standard questions: Where are you now? who are you playing? What’s the score? Then she might administer a balance test, counting the player’s mistakes as he stands with his feet together, on one (non-dominant) foot, and with one foot behind the other. those balance tests have been baselined as well for Casa Grande students.

The on-the-spot tests are the best Campbell can do in the heat of competition, but they aren’t comprehensive enough to guide long-term treatment. and athletes’ self-evaluations are notoriously unreliable, because many of them will do practically anything to prove their toughness and get back on the field.

The data-driven evaluations are better for everybody. Campbell, the Casa Grande coaches and the kids’ families can be more confident in allowing the athletes to play, and the school district can minimize its liability.

“I’m lucky,” Campbell said. “The coaches are 100 percent behind me, and I’ve never had a parent say anything about it — just ‘we’re glad you’re here.’”

Students aren’t always thrilled when they have to sit out, but that’s part of the new reality of concussion management. as Campbell tells them: “I’m doing this not so I can pull you from the field, but so I can get you back faster.”

The Concussion Vital Signs program got a late start at Casa this year. Overseeing 15 to 20 kids at a time in the computer lab, Campbell was able to get nearly every football player tested before the Gauchos’ first game. but she didn’t complete the boys’ soccer baselines until the third week of the season, and girls’ soccer wasn’t done until the midway point. The program has helped identify at least three football players and two boys’ soccer players with concussions.

Campbell should be on better footing for basketball and wrestling. Next summer, she hopes to have every football player tested before they put pads on.

A former basketball standout at Petaluma (her father, Ed Iacopi, was a long-time coach at Casa Grande), Campbell would like to see the web-based program expanded to other high schools. Of course, it would help if other campuses had certified athletic trainers.

She takes so much off my plate,” Gauchos football coach Trent Herzog said. “when it comes to injuries and preventing injuries, I don’t even worry about that. … before the Petaluma game, I happened to see their head coach. It’s 45 minutes before kickoff, and he is taping players. I’ve never had to worry about taping ankles. I’m focused on my game plan.”

The Casa coaches coach, the players play and the doctors diagnose. and Heather Campbell and her concussion-monitoring program make it a little easier for all of them.