ImPact Test-Retest Reliability: Reliably Unreliable?

This study is an observational study of the reliability of follow up tests. In my personal opinion, ANY patient who is SYMPTOMATIC but has a normal test AND any ASYMPTOMATIC patient with an abnormal test should have an expert evaluation .

Do experts review all these baseline tests and provide an interpretation?

Do parents get results and an option to evaluate their child?
Are schools  putting students with abnormal tests in the game?

hmmm...

 JR

ImPact Test-Retest Reliability: Reliably Unreliable?

Jacob Resch , PhD, ATC*; Aoife Driscoll , BSc†; Noel McCaffrey , MD†; Cathleen Brown , PhD, ATC‡; Michael S. Ferrara , PhD, ATC, FNATA‡; Stephen Macciocchi , PhD, ABPP§; Ted Baumgartner , PhD‡; Kimberly Walpert , MD‖

*University of Texas at Arlington;

†Dublin City University, Ireland;

‡University of Georgia, Athens;

§Shepherd Center, Atlanta, GA;

‖Georgia Neurological Surgery, Athens

Context: Computerized neuropsychological testing is commonly used in the assessment and management of sport-related concussion. Even though computerized testing is widespread, psychometric evidence for test-retest reliability is somewhat limited. Additional evidence for test-retest reliability is needed to optimize clinical decision making after concussion.

Objective: To document test-retest reliability for a commercially available computerized neuropsychological test battery (ImPACT) using 2 different clinically relevant time intervals.

Design: Cross-sectional study.

Setting: Two research laboratories.

Patients or Other Participants: Group 1 (n = 46) consisted of 25 men and 21 women (age = 22.4 ± 1.89 years). Group 2 (n = 45) consisted of 17 men and 28 women (age = 20.9 ± 1.72 years).

Intervention(s): Both groups completed ImPACT forms 1, 2, and 3, which were delivered sequentially either at 1-week intervals (group 1) or at baseline, day 45, and day 50 (group 2). Group 2 also completed the Green Word Memory Test (WMT) as a measure of effort.

Main Outcome Measures: Intraclass correlation coefficients (ICCs) were calculated for the composite scores of ImPACT between time points. Repeated-measures analysis of variance was used to evaluate changes in ImPACT and WMT results over time.

Results: The ICC values for group 1 ranged from 0.26 to 0.88 for the 4 ImPACT composite scores. The ICC values for group 2 ranged from 0.37 to 0.76. In group 1, ImPACT classified 37.0% and 46.0% of healthy participants as impaired at time points 2 and 3, respectively. In group 2, ImPACT classified 22.2% and 28.9% of healthy participants as impaired at time points 2 and 3, respectively.

Conclusions: We found variable test-retest reliability for ImPACT metrics. Visual motor speed and reaction time demonstrated greater reliability than verbal and visual memory. Our current data support a multifaceted approach to concussion assessment using clinical examinations, symptom reports, cognitive testing, and balance assessment.

Key Words:  intraclass correlation, concussions, mild traumatic brain injuries, neuropsychological 
testing, athletes

FULL study here

Address correspondence to Jacob Resch, PhD, ATC, University of Texas at Arlington, Box 19259, 113 Maverick Activities Center, Arlington, TX 76102. Address e-mail to resch@uta.edu.

Concussions can happen to all children, not just the athletes

This article discusses how concussions are possible in all children, not only the ones who are in football or other sports.

The gridiron is back in action. From little leagues to professional teams, football frenzy has begun, and with it, concerns about concussions. But it's not just jarring tackles that can lead to concussions in kids. According to Dr. Ryan Coates, pediatric neurologist at Loyola University Health System, there are many ways kids are exposed to concussion risks.

"We hear a lot about concussions when it comes to sports and we should be on the lookout for head injuries, but athletes aren't the only ones who are at-risk for brain trauma," said Coates.

Concussions are a result of a traumatic brain injury that causes a disruption of the brain function. Disruption of neurologic function can manifest itself with a multitude of symptoms, including headache, loss of consciousness, concentration and memory disturbances, dizziness, nausea/vomiting and confusion.

"What symptoms a person experiences depends on how the brain moves within the skull as a result of the injury," said Coates. "Everyone is different and how a person responds after brain trauma is variable. Symptoms can last for a few hours or several months." Coates said very young children are the most at risk for brain trauma because they have less protection.

"Young children are more dependent on caregivers to keep them safe and don't have as many ways of protecting themselves from falls and accidents as adults and older children," said Coats.

Falls are the leading cause of traumatic brain injury in the country, according to the Centers for Disease Control and Prevention. Also, nearly half of the traumatic brain injuries in children are from a fall.

"Parents need to watch their children carefully, especially around stairs and at the playground. Make sure your child isn't doing something that isn't age appropriate," said Coates. "Following safety guidelines for car seats is important for keeping kids safe as well."

Traumatic brain injuries and concussions shouldn't be taken lightly. Timely recognition and appropriate response are vital. Any child who has had a concussion should be seen by a physician within 24 hours and have a complete neurological exam.

"Even one concussion can have long-term effects, including learning difficulties and other issues that impact quality of life," said Coates.

Though all kids are susceptible to concussions, special attention does need to be given to kids participating in sports. According to Coates, it's imperative that coaches, supervisors and parents are all on the same page when it comes to brain injuries.

"Any child who has a head injury, even if it seems minor, should immediately be taken out of the event. Symptoms can happen immediately or even days after the injury, so don't take any chances. A child's brain function is more important than the next play," said Coates. "No one is immune to head injuries. Just because someone has had head trauma before and didn't have any apparent issues doesn't mean the next hit won't cause substantial injury and long-term effects."

Read more here

• Article

Neurodegenerative causes of death among retired National Football League players

1. Everett J. Lehman, MS, 
2. Misty J. Hein, PhD, 
3. Sherry L. Baron, MD and
4. Christine M. Gersic

+Author Affiliations

1. From the Centers for Disease Control and Prevention, The National Institute for Occupational Safety and Health, Division of Surveillance, Hazard Evaluations and Field Studies, Cincinnati, OH.

1. Correspondence & reprint requests to Mr. Lehman: elehman@cdc.gov

View Complete Disclosures

ABSTRACT

Objective: To analyze neurodegenerative causes of death, specifically Alzheimer disease (AD), Parkinson disease, and amyotrophic lateral sclerosis (ALS), among a cohort of professional football players.

Methods: This was a cohort mortality study of 3,439 National Football League players with at least 5 pension-credited playing seasons from 1959 to 1988. Vital status was ascertained through 2007. For analysis purposes, players were placed into 2 strata based on characteristics of position played: nonspeed players (linemen) and speed players (all other positions except punter/kicker). External comparisons with the US population used standardized mortality ratios (SMRs); internal comparisons between speed and nonspeed player positions used standardized rate ratios (SRRs).

Results: Overall player mortality compared with that of the US population was reduced (SMR 0.53, 95% confidence interval [CI] 0.48–0.59). Neurodegenerative mortality was increased using both underlying cause of death rate files (SMR 2.83, 95% CI 1.36–5.21) and multiple cause of death (MCOD) rate files (SMR 3.26, 95% CI 1.90–5.22). Of the neurodegenerative causes, results were elevated (using MCOD rates) for both ALS (SMR 4.31, 95% CI 1.73–8.87) and AD (SMR 3.86, 95% CI 1.55–7.95). In internal analysis (using MCOD rates), higher neurodegenerative mortality was observed among players in speed positions compared with players in nonspeed positions (SRR 3.29, 95% CI 0.92–11.7).

Conclusions: The neurodegenerative mortality of this cohort is 3 times higher than that of the general US population; that for 2 of the major neurodegenerative subcategories, AD and ALS, is 4 times higher. These results are consistent with recent studies that suggest an increased risk of neurodegenerative disease among football players.

• Received April 24, 2012.
• Accepted July 9, 2012.

• Copyright © 2012 by AAN Enterprises, Inc.

Football players more likely to develop neurodegenerative disease, study finds

Football players more likely to develop neurodegenerative disease, study finds(CNN) -- Just hours before the 2012 NFL season kicks off, a new study suggests that professional football players are three times more likely to have neurodegenerative diseases than the general population.

When researchers specifically looked at Alzheimer's disease and ALS -- amyotrophic lateral sclerosis, also known as Lou Gehrig's disease -- that risk increased to four times greater than the rest of us.

The study, published Wednesday in the medical journal Neurology, surveyed nearly 3,500 retired NFL players who were in the league between 1959 and 1988.

The National Institute for Occupational Safety and Health, a division of the Centers for Disease Control, had been following this group of players since the early '90s, when the NFL asked the institute to evaluate them for their risk of cardiovascular disease.

This time, the authors decided to look at the neurological outcomes of the players by specifically evaluating the autopsies of 334 players.

CNN article here

Five Ways to Prevent a Concussion in Your Teenage Athlete - Pediatric Neurologists Share Tips to Help Reduce Concussions in Children and Teenagers

Five Ways to Prevent a Concussion in Your Teenage Athlete

 - Pediatric Neurologists Share Tips to Help Reduce Brain Injuries in Children & Teenagers

Houston, TX August 07, 2012

Your son leaves for his football game. Your daughter is off for soccer practice. Two hours later, the team trainer calls home to report that your teenager is in the ER, having suffered a concussion.

What can a parent do today to prevent a concussion in a child or teenager? Here is advice from four child neurologists, experts in the management of traumatic brain injury.

Dr. Joshua Rotenberg, a pediatric neurologist in Houston and San Antonio (http://www.txmss.com), advises parents, “Before letting your child or teen take the field, review your own game-plan for concussion prevention.”

Here are 5 Pre-Season Action Items for parents of athletes:

#5 Increase Subject Matter Knowledge - The presentation of concussion can be subtle and a child may not recognize it in themselves. With knowledge, one can prevent concussion or at least prevent complications.

Dr. Kevin Joseph of Valley Medical Center/University of Washington Medicine advises families and athletes to learn about the symptoms of concussion.

Concussion symptoms can take the form of almost any disturbance of brain function. These can include any combination of physical (headache, dizziness, ringing in ears, nausea/vomiting, blurry vision, weakness), emotional (depression, anxiety), cognitive (memory problems, focus problems) and sleep disturbances (insomnia, excessive sleepiness).

Concussion can be caused by a direct head trauma or indirectly by a sudden impulse of energy. That is, a concussion is not necessarily caused by a recognizable head-to-head impact.

Concussion does not only happen to male football players! Current estimates are that up to 20% of high school football players will sustain a concussion in a season. But, women’s soccer is the second most likely school sport to cause a concussion.

Other activities more likely to cause traumatic brain injury in teens are bicycling, basketball, volleyball and cheer. Even non-athletes are susceptible to falls and accidents.

Among athletes, who is at high risk? Concussion risk factors include prior concussion and neuropsychological problems such as Attention Deficit Hyperactivity Disorder (ADHD).

One study indicated that 26% of children with ADHD had sustained a head injury. Ensure that ADHD treatment is adequate to prevent impulsive or distracted performance.

Children who have sustained a previous concussion are up to 6 times more likely to have a subsequent concussion. For children and teens who have suffered multiple concussions, ensure that they have seen a specialist and they are cleared for full contact activity.

#4 Check Protective Equipment - Ensure that athletes have a current and highly rated helmet that also has an appropriate fit.

Dr. Marc Difazio, a child neurologist at Children’s National Medical Center, Washington DC, notes, “Safe helmet systems go far to prevent concussion. Football, lacrosse and hockey players can obtain effective helmets that greatly decrease the force of the impact of a blow.”

There are helmet systems for soccer players that do not interfere with the ability to head the ball (not a major cause of concussion by the way!). These systems can certainly be used in other contact sports (such as field hockey), which do not require a helmet.

Mouth guards are important for preventing oral trauma, but have not been shown to reduce concussion.

Consult a certified athletic trainer to ensure your equipment has an optimal fit.

#3 Ensure Adequate Training - Young athletes require general athletic training and sport specific technique

Dr. Marc Difazio observes, “Unrestricted head movement is one component of concussion physics. Strength training for head, neck and shoulders of young athletes helps to deliver more precise control of their bodies, possibly lessening the movements associated with impact, and potentially decreasing concussion risk.”

Proper training in football and rugby tackling is crucial. Tackling technique in football must be taught from the start, and dangerous head-on methods discouraged immediately.

Heading the ball appropriately in soccer has not been shown to cause concussion if done correctly. However, Dr. Difazio has observed that “novice players may not perform the technique appropriately, leading to excessive head movement and a resultant risk of concussion. Teaching correct heading techniques is therefore as important as kicking, dribbling and game strategy."

#2 Heighten Parental Vigilance - You are entrusting your child’s brain to coaches and trainers. Most are excellent stewards of this trust. But, even with the best trainer and coach, you are the expert on your child.

Be present and vigilant about your child’s participation. Ask about style and contact of practices and games. Valid questions include: Are freshmen scrimmaging with seniors? Who cares for the equipment? How do they fit?

Dr. Joseph advises, “Know who is responsible for responding to head injuries at the game....Know what the school or organization policy is regarding head injuries (what happens on game day and when can the child return to play).”

Youth sports can be less regulated than interscholastic school sports. Do youth football players have more aggressive collision in practice than in games? Perhaps! One recent study indicated that concussive head injury in youth football may be more common in practice than in the game. If you note atypical practice or game activities, discuss these with the coach and trainers.

Most importantly, you know your child best. You may detect cognitive, behavior or performance abnormalities before anyone else does. Keep a low threshold to suspect concussion. Parental observation and symptom identification are key to diagnosis.

In many states, there are concussion laws describing how school athletes must be removed from play or practice if concussion is suspected. Note that this is a low threshold.

If you suspect a head injury, for whatever reason, have your child evaluated and let the physicians sort it out. Missing one game or practice is better than missing weeks of participation.

# 1 Form an action plan in case of concussion!

Reassuringly, concussions most often resolve quickly and completely within a couple of weeks. The majority of children and teens suffer no long term implications.

At the same time, keep in mind what you would do following a severe injury or a deteriorating situation. An emergency evaluation may be necessary in severe or deteriorating head injury cases. Following a head injury, if the little voice inside you is telling you to go to the emergency room, listen to that voice.

Children with concussion should see a physician. Make sure to visit your primary care physician. The doctor who knows your child might also be able to detect differences that a parent missed.

To meet the need for rapid access to pediatric brain specialists, these neurologists offer expedited evaluations.

Dr. Rotenberg advises seeking the highest possible level of expertise in the identification and management of brain injury for children “The symptoms and signs of concussion are physical, neurologic and neuropsychological. It is important to seek a child and adolescent neurologist’s advice since a specialist can identify serious head injury, diagnose concussion and treat its complications”.

Remember, a computerized test alone can not establish a diagnosis of concussion. “You can purchase an online test or go to a retail store. But is it valid or useful?” asks Rotenberg. Variables such as the setting, motivation and the specifics of the test must be considered with the whole person

Finally, Dr. Rotenberg advises all parents, “Ensure that all children have an adequate pre-season physical examination by a physician who knows your child.”

Drs. Rotenberg, Joseph and DiFazio serve on a pediatric working group for sports neurology. Texas Medical & Sleep Specialists serves the Houston and San Antonio areas with pediatric neurology and specialty care. Contact Dr. Rotenberg at 713-464-4107 or read more at his blog http://www.pedzzz.blogspot.com.

http://www.chron.com/business/press-releases//business/press-releases/article/Five-Ways-to-Prevent-a-Concussion-in-Your-Teenage-3769750.php

I am happy to see changes to football practice policies based on data of childhood head impacts. JR

Amidst Concern About Head Injuries, Youth Football League Issues New Practice Rules

see article by 

June 14, 2012, 4:13 pm ET by Gretchen Gavett

Football has never been more popular. But is it worth the risks? Watch FRONTLINE’sFootball High for more on head injuries, heatstroke and other issues facing young athletes.

Starting in August, Pop Warner youth football league practices will likely look a bit different.

The league announced yesterday that it’s revamping its practice rules in response toincreased concern about head injuries in football. The rules include:

• A ban on full speed head-on blocking or tackling drills when players line up more than 3 yards away from one another. Intentional helmet-to-helmet hits are not allowed.
• A limit on hits during practice. Only one-third of practice time per week can be devoted to drills that use contact, which breaks down to about 40 minutes per practice.

In a press release about the revamp, Pop Warner also reiterated that certain blocking and tackling techniques, including face tacking and spearing, remain prohibited. The league is in the process of updating its website to include easily accessible information about concussions and safety.

Full article here

Virginia Tech researchers placed helmets with sensors on 7- and 8-year-old football players and collected data on more than 750 hits to the head over a season. The findings are the first quantitative study of the acceleration and risk that young brains face in youth football. Special correspondent Stone Phillips reports.

Initial report here

Academic effects of contact sports on college athletes

Cognitive effects of one season of head impacts in a cohort of collegiate contact sport athletes

While it is known that concussions can harm an athlete’s ability to learn, a new study has found evidence that even one season of contact sports can affect how well some athletes acquire new information, according to the study’s lead author and Director of Neuropsychiatry at the Geisel School of Medicine Thomas McAllister.

The research was part of a multi-institution study that has been working for five or six years to understand the biomechanical basis and effects for concussions, McAllister said.
The study, which was published by the American Academy of Neurology, found that contact sport athletes did not perform worse than non-contact sports athletes on cognitive tests before their seasons began. These results were “reassuring,” McAllister said.

“We did not find any systematic widespread adverse affects on cognition,” he said. “The two groups on average looked pretty similar at the end of the season.”

The study did find that a larger subgroup of contact sport athletes than non-contact sports athletes performed worse than expected on tests taken immediately after the season. Taking into account how well the athletes tested before their season began and controlling for other indicators of general test performance and the interval between tests, the authors predicted how well the athletes should perform after their season and compared this to their actual results.

“We found that about 22 percent [of contact sport athletes] did worse than 1.5 standard deviations below what we would have predicted,” McAllister said. “This was a significant difference from the non-contact group.”

McAllister said that this raises the possibility that some individuals are particularly vulnerable to suffering negative effects from hitting their heads repeatedly during contact sports.
“This changes the emphasis of the debate a little bit,” McAllister said. “It’s a new direction for us to be thinking about the risks or lack of risks for contact sports. There may not be the same risk for everyone.”

The researchers also used the tests administered at the beginning of the season to see whether athletes who had been playing contact sports for most of their lives and had presumably hit their head more often had lower cognition than non-contact sport athletes.
“We did not find any systematic differences between the two athlete groups at the beginning of the season,” McAllister said. “We think this is good news. We were unable to detect widespread significant differences in their cognitive capabilities.”

To measure their results, researchers administered two tests to male and female contact and non-contact sport athletes from the College, Brown University and Virginia Polytechnic Institute and State University at the beginning and end of their seasons. Contact sport athletes played football or ice hockey while non-contact sport athletes participated in track, Nordic skiing or crew.

Participants that sustained a documented concussion during the season were not included in the study results because researchers were primarily interested in the effects of “repetitive impacts to the head not apparently causing a concussion,” according to McAllister.
A 20-minute computerized test measured cognition, memory attention and reaction time. The other neurological test, administered to a sub-group of athletes, was more extensive and used “paper and pencil.” Researchers compared the results of the contact sport athletes’ tests with the non-contact sport athletes’ tests, which were used as a control.
Contact sport athletes wore special helmets during practice and games equipped with a Head Impact Telemetry System designed by Richard Greenwald, the president of Simbex, a technology company in Lebanon. The helmets have been in use since 2004 around the United States, according to Greenwald.

“The helmets contain a system that monitors head impacts automatically and wirelessly,” Greenwald said. “They measure how often, how hard and where on the helmet gets hit.”
Jessica Gagner ’13 plays women’s ice hockey and participated in the study as a contact sport athlete. She said she was not more cognizant about hitting her head when wearing the helmet.

“To me, if you’re playing a contact sport, you’re obviously going have a bigger effect on your head,” Gagner said. “It’s really inevitable that you’re going to have more of an issue with head impacts if you are a contact sport athlete.”
Cara Vernacchia ’13 runs track and was a non-contact athlete who participated in the study. She said she was glad to be able to take part to help researchers learn more about concussions and how to prevent them.

“Being able to be part of the study made me realize that concussions do occur,” Vernacchia said. “It’s interesting to see how prominent head impacts are, even on our campus.”
The researchers hope to continue observing the effects of contact sports on the study’s participants. Many students agreed to undergo neuroimaging before and after their seasons and researchers hope to examine these results.

“We’d love to be able to revisit with some of these athletes four or five years down line and get a second set of test results to see how they’re doing after a whole collegiate career,” McAllister said.

The researchers also hope to learn more about why certain athletes performed worse than expected on tests after a season of contact sports.
“I think the second theme of ongoing research would be to try and understand what individuals are at risk to be in that ‘not doing as well as we would have thought’ category,” McAllister said.

Greenwald said that the researchers hope to learn more about the effects of contact sports on youth and women in the future.

Read more here:

Cognitive effects of one season of head impacts in a cohort of collegiate contact sport athletes

1. T.W. McAllister, MD, 
2. L.A. Flashman, PhD, 
3. A. Maerlender, PhD, 
4. R.M. Greenwald, PhD,
5. J.G. Beckwith, MS, 
6. T.D. Tosteson, ScD, 
7. J.J. Crisco, PhD, 
8. P.G. Brolinson, DO,
9. S.M. Duma, PhD, 
10. A.-C. Duhaime, MD, 
11. M.R. Grove, MS and 
12. J.H. Turco, MD

+Author Affiliations

1. From the Departments of Psychiatry (T.W.M., L.A.F., A.M., M.R.G.), Community and Family Medicine (T.D.T.), and Medicine (J.H.T.), Dartmouth Medical School, Lebanon; Simbex (R.M.G., J.G.B.), Lebanon; Thayer School of Engineering (R.M.G.), Dartmouth College, Hanover, NH; Bioengineering Laboratory, Department of Orthopaedics (J.J.C.), The Warren Alpert Medical School of Brown University and Rhode Island Hospital, Providence, RI; Edward Via Virginia College of Osteopathic Medicine (P.G.B.), Blacksburg; Virginia Tech-Wake Forest (S.M.D.), Center for Injury Biomechanics, Blacksburg; Pediatric Neurosurgery (A.-C.D.), Children's Hospital at Dartmouth, Dartmouth Hitchcock Medical Center, Hanover, NH; and Pediatric Neurosurgery (A.-C.D.), Massachusetts General Hospital, Boston.

1. Correspondence & reprint requests to Dr. McAllister: thomas.w.mcallister@dartmouth.edu

View Complete Disclosures

ABSTRACT

Objective: To determine whether exposure to repetitive head impacts over a single season negatively affects cognitive performance in collegiate contact sport athletes.

Methods: This is a prospective cohort study at 3 Division I National Collegiate Athletic Association athletic programs. Participants were 214 Division I college varsity football and ice hockey players who wore instrumented helmets that recorded the acceleration-time history of the head following impact, and 45 noncontact sport athletes. All athletes were assessed prior to and shortly after the season with a cognitive screening battery (ImPACT) and a subgroup of athletes also were assessed with 7 measures from a neuropsychological test battery.

Results: Few cognitive differences were found between the athlete groups at the preseason or postseason assessments. However, a higher percentage of the contact sport athletes performed more poorly than predicted postseason on a measure of new learning (California Verbal Learning Test) compared to the noncontact athletes (24% vs 3.6%; p < 0.006). On 2 postseason cognitive measures (ImPACT Reaction Time and Trails 4/B), poorer performance was significantly associated with higher scores on several head impact exposure metrics.

Conclusion: Repetitive head impacts over the course of a single season may negatively impact learning in some collegiate athletes. Further work is needed to assess whether such effects are short term or persistent.