Understanding Concussion Assessment and Evaluation

1
Understanding Concussion Assessment and Evaluation

• Philip Schatz, PhD
• Saint Josephs University, Philadelphia
  PApschatz_at_sju.edu

2
Cerebral Concussion

• Mild traumatic brain injury
• Alteration in consciousness due to a blow to the
  head or acceleration/deceleration/rotational
  force
• Does NOT imply or require loss of consciousness.
• Usually temporary changes in mental status
• Temporary changes in somatic functioning
• May produce a wide range of symptoms
• Normal structural neuroimaging CISG, Vienna
  (2001) Prague (2004)

3
Post Concussion Symptoms
Oh man I was licking the dreamsicle --
Professional wrestler, reflecting on a concussion
Head Games Chris Nowinski
4
Post Concussion Symptoms

• Physical
• Pressure in head
• Headache
• Balance troubles
• Visual Disturbance
• Numbness
• Tingling
• Feeling slow
• Sensitivity to light/noise

• Psychological
• Feeling like in a fog
• Difficulty concentrating
• Difficulty remembering
• Irritability
• Sadness
• Nervousness

5
COMMONLY REPORTED SYMPTOMSHigh School/University
Athletes within 3 days of injury

• Headache (71)
• Feeling slowed down (58)
• Difficulty concentrating (57)
• Dizziness (55)
• Fogginess (53)
• Fatigue (50)
• Visual Blurring or double vision (49)
• Light sensitivity (47)
• Memory dysfunction (43)
• Balance problems (43)

6
Physiological Changes

• Shearing or strain injury of axons
• Diffuse microscopic changes to axons
• Microscopic tearing of small blood vessels
• Metabolic cascade resulting in imbalance between
  glucose demands and regional CBF supply
  (vulnerable to SIS) Giza Hovda, JAT, 36(3),
  228-35

7
Neurometabolic Changes
8
Incidence of Mild TBI

• 75 to 85 of all head injuries
• 1.0 to 1.5 million cases per year in US
• 300,000 from sports (an underestimate?)
• Most cases go unreported

9
Incidence of Mild TBI

• Question What sport has the highest incidence
  of concussion (if you know, dont say it)

10
Previous Findings Epidemiology

• By Sport

SPORT RANGE Equestrian 3 - 91 Boxing 1 -
70 Rugby 2 - 25 Soccer 4 - 22 Football 2 -
20 Bicycling 0 - 13.8 Martial Arts 0 - 11 Auto
Racing 0 - 10.5 Ice Hockey 3 - 7.5
Ruchinskas, et al., 1997, Applied Neuropsych
11
Epidemiology Issues (Macciocchi)

• Recognition one occurred may be easier then
  measuring concussion severity
• Diagnosis for epidemiological purposes may be
  more difficult than it seems
• Discrepancy between of players reporting and
  the who believed they sustained one
• Post-season, players reported symptoms but didnt
  connect them to concussive injuries
• 70 of football and 63 of soccer players
  reported post-concussion symptoms

12
Epidemiology Methods (Macciocchi)

• Quasi-experimental comparison- athletes examined
  pre-season, followed for a period of time
• Look at of concussions sustained over that
  period
• Generalize from cohort to population
• Use date from surveillance systems
• Monitor concussive injuries on a broader scale
• Sometimes are organization-based, such as NCAA

13
Epidemiology Terminology (Macciocchi)

• Athletic Exposure (AE)
• Period of time when an athlete could have
  sustained an injury, such as practice or game
• Confounded by time (a 5-minutes shift is the same
  as an entire game)
• Injury Rate (IR)
• Number of injuries incurred relative to the total
  number of exposures
• Often stated as per 1000 AEs

14
Epidemiology High School

• 20 or 250,000 per year in football (Gerberich,
  et al. 1985)
• 25,520 per season (Powell, 1995)
• NATA High School Study
• 57,716 occurrences of mTBI per year
• 5.3 of football injuries
• 4.4 of wrestling injuries
• 3.4 of boys soccer
• 2.6 girls soccer
• 2.3 girls basketball

15
Epidemiology NCAA

• College NCAA Injury Surveillance System
• 1.6 to 6.4 of all injuries
• Ice Hockey - 4.5 of all injuries (.56 per 1,000
  AE)
• Football .43 per 1,000 AE
• Wrestling .49 per 1,000 AE
• Soccer (Men .35/Women.58)
• Lacrosse (Men .33/Women.62)
• Basketball (Men.16.Women.29)

16
Concussion Base Rates

• History of Previous Concussion 10-80
• Recent Trend Upwards
• ( with 1 Previous Concussion)
• Collins, et al (1999) 53
• Kaushik (2005) 75
• Moser, Schatz, Jordan (2005) 63
• Different breed of youth athletes in 2000s vs.
  1980s?

17
What about Gender?Hillary, Mann, Schatz, ACN,
2002
Study Sport ( of All Injuries)
Males Females Powell, Barber-Foss
Soccer 3.9 4.3 Powell, Barber-Foss
Basketball 2.6 3.6 Powell, Barber-Foss Basebal
l/Softball 1.7 2.7 NCAA Soccer 4.7 4.4 Tot
al of all injuries 3.23 3.75 Study Sport
(Injuries per 1000 AE) Males Females Dick Soccer
0.348 0.578 Dick Lacrosse 0.334 0.618 Boden,
et al. Soccer 0.6 0.4 NCAA Soccer 0.44 0.46 Powe
ll, Barber-Foss Soccer 0.18 0.23 Powell,
Barber-Foss Basketball 0.11 0.16 Powell,
Barber-Foss Baseball/Softball 0.05 0.1 J. Kelly,
J. Rosenberg Soccer 0.25 0.24 Total Ave per
1000 AE 0.289 0.348 Soccer Ave per 1000
AE 0.364 0.382 Other Ave per 1000
AE 0.165 0.293

18
Epidemiology GenderCovassin, Swanik, Sachs,
JAT, 2003)

• NCAA Injury Surveillance System 3-year study
• Of 14,591 reported injuries, 5.9 were
  classified as concussions
• Concussions during practices
• Female athletes 167 (3.6) Male
  athletes 148 (5.2)
• Concussions during games
• Female athletes 304 (9.5)
• Male athletes 254 (6.4)

19
Epidemiology GenderCovassin, Swanik, Sachs,
JAT, 2003)

• Barnes, et al, 1998, Am J Sports Med
• Female athletes could be at more risk due to
  their smaller size or greater ball-to-head size
  ratio.
• Female athletes may have weaker neck muscles
  than male athletes.
• Boden et al, 1998, Am J Sports Med
• Male athletes may be more skilled at protecting
  their heads from injury, but there are no data to
  support this hypothesis.

20
Gender Differences at Baseline

• 1209 NCAA Division 1 Athletes - 5 Northeastern
  Universities
• Completed ImPACT at baseline
• Female athletes performed significantly better
  than male athletes on baseline verbal memory
  scores (p 0.001)
• Male athletes performed significantly better
  than female athletes on baseline visual memory
  scores (p 0.001).
• Covassin, Swanik, Sachs, Kendrick, Schatz,
  Zillmer, Kaminaris, (BJSM, 2007)

21
Gender Differences at Baseline

• Female athletes endorsed a significant number of
  mild baseline symptoms as compared to male
  athletes
• Headache, nausea, fatigue, need more sleep,
  drowsiness, sensitive to noise, sadness,
  nervousness, more emotional, difficulty
  concentrating, visual problems.
• Effect sizes ranged from .13 (Sleep) to .40
  (Emotional)Covassin, Swanik, Sachs, Kendrick,
  Schatz, Zillmer, Kaminaris, (BJSM, 2007)

22
Recommended schedule for measuring
post-concussion status
NP Testing
RETURN TO PLAY?
Sideline Testing
BASELINE NP TESTING
INJURY
1-2 DAYS AFTER INJURY
PRE-SEASON
23
Historical Aspects UVA Football Study - Barth,
et al., 1989
Trail Making B Pre-Season and Post-Injury
Performances
24
Historical Aspects Neuropsych Measures-Trails B
25
Historical Aspects Neuropsych Measures-Digit
Symbol
26
Historical Aspects Neuropsych Measures - PASAT
27
Historical Aspects Neuropsych Measures - COWAT
Tell me as many words that you can think of that
start with the letter FAS.
28
Historical Aspects Neuropsych Measures - STROOP
29
Historical Aspects Neuropsych Measures - STROOP
30
Historical Aspects Neuropsych Measures - STROOP
31
Historical Aspects Neuropsych Measures - STROOP
32
Historical Aspects UVA Football Study - Barth,
et al., 1989
PASAT-4 Pre-Season and Post-Injury Performances
33
Historical Aspects Echemendia PSU Hockey COWAT
34
Historical Aspects

• Egocentric view
• The Virginia Football Study
• Echemendias PSU Program
• Saint Josephs University
• Division I, No Football, 400 varsity athletes
• Where can I find a place?
• Computers circa 1998

35
What We Knew 2000

• Effects of Cerebral Concussions last up to 7-10
  days
• Primarily attention and concentrationAlves,
  Rimel, Nelson, 1987, Clinical Sports Medicine,
  6(1), 211-8Barth, et al., 1989, in H. Levins
  Mild Head Injury Oxford Press
• Effects of cerebral concussions last up to 30
  days and beyond (Echemendia, et al., 1999)
• Extends to other cognitive processesEchemendia
  Julian, 2001, NP Review 11(2), 69-88

36
What We Knew 2000

• LOC is not a predictor of concussion, and
  incidence of LOC does not effect cognitive
  performance (Lovell, et al, J. Clin Sports Med,
  1999)
• Individuals with history of Concussion and/or
  Learning Disability show lowered baseline
  performance on testing. (Collins, et al., JAMA,
  1999)

37
Current Research How do I develop a Concussion
Program at SJU?
(Hopefully) based on Professional and Collegiate
Concussion Management Programs

• NFL - Majority
• NHL - Mandatory
• Baseline, Serial Post-concussion Evals.
• Wide Network of Neuropsychologists
• Colleges test teams pre-season

38
SJU Concussion Pilot Study Trails B
39
SJU Concussion Pilot Digit-Symbol
40
SJU Concussion Pilot Study d2
41
There already was a trend towards computer-based
assessment

• CRI (HeadMinder.com). 1999
• Web based
• CogSport (CogState.com)..1999
• Windows/Mac
• ImPACT (ImPACTtest.com). 2000
• Windows based

42
Why should we opt for computer-based assessment?

• Sensitive to RT, Processing Speed
• Randomized Trials Improved reliability
• Ability to test entire team at once (benefit?)
• Better/Objective date for Athletic Trainers, Team
  Physicians
• Assistance with Return to play decisions (Schatz
  Zillmer, 2003, Applied Neuropsych Schatz
  Browndyke, 2003, JHTR)

43
Why should we not opt for computer-based
assessment?

• Perhaps timing is not millisecond-accurate
• Limited validation with np standards
• Little qualitative or verbal data
• Can be used by Athletic Trainers, Team Physicians
  in absence of Neuropsych
• May determine return to play decisions (Schatz
  Zillmer, 2003, Applied Neuropsych)

44
Theres a whole lot of post-concussion tests and
schedules
Comparison of Post-concussion Assessment
Schedules and Measures. (From McKeever Schatz,
Applied Neuropsychology, 10, 2003) Schedule of
Serial Post-Concussion Assessments Hours Days
Study 1-2 24-48 3 5 7 10 30 Measures
Used NCAA- Multiple sports 2 24 7 30 cPC,
dHVLT, fSDMT, gStroop, hTrails, jVIGIL/W,
(Echmendia, et al., 2001) kDig. Span,
lPSU,mCOWAT NCAA-Football 1 3 5 7 dHVLT,
hTrails, kDig. Span, fSDMT, mCOWAT, (Collins,
et al., 1999) nPegboard NCAA-Football 24
5 10 eSDMT, hTrails, oPASAT (Barth, et al.,
1989) Prof. Hockey Players 24 5b 7b cPC,
dHVLT, fSDMT, iTrails, lPSU, mCOWAT,
(Echemendia, 2001) pBVMT-R Prof.
Football Players 24 5 dHVLT, fSDMT, hTrails,
kDig. Span, mCOWAT, (Lovell Collins,
1998) nPegboard Prof. Rugby
Players 1 5 eSDMT, rChoice RT., rMemory,
rOrientation (McCrory, et al., 1997) Prof. Rugby
Players 3a 7a 35 a eSDMT, qDigit Symbol,
rSpeed of Comprehension (Hinton-Bayre, et al.,
1999) aAthletes tested 1 to 3
days, 1-2weeks, 3-5 weeks post-concussion
bAthletes tested 5 to 7 days post-concussion
45
Power In NumbersPhiladelphia Sports Concussion
Program

• Mandatory for Participation in Athletics
• Drexel, Temple, SJU Delaware, Rutgers
• Baseline, 24-48 hr, 3, 5, 7, 10, weekly if Sx
• ImPACT _at_ 4 schools, CRI _at_ Temple
• Dissertations (McKeever, Covassin, Schneider),
  Masters Theses
• Validate multiple measures(ImPACT, CRI,
  CogSport, Trails, Digit Symbol, d2)
• Gender, Sport, History, Club Sports,
  Cheerleaders, School Norms

46
Cross-Validation of Computer-Based Measures -
Rationale(Schatz Putz, Applied Neuropsych 2006)

• Limited shared validation of existing
  computer-based measures with standards
• SDMT correlates with
• ImPACT Processing Speed (r.70) and Reaction Time
  (r-.60)
• CRI Processing Speed (r.60, r.67)
• Trails correlates with
• CRI Response Speed (A r.73 B r.74)
• CRI Processing Speed (B r.37)
• CogSport Complex RT (B r.34)
• CogSport Simple RT (B r.44)

47
Cross-Validation of Computer-Based Measures -
Methodology

• 30 Normal Volunteers
• Computer-based ImPACT, CRI, CogSport, d2, Trails
  AB, Digit Symbol
• Paper-based Trails AB, Digit Symbol
• Administration MWF, Individually
• Grouping A ImPACT, d2 Test of Attention
  (computerized)
• Grouping B CRI, Trails A and B. and Digit Symbol
  (pencil and paper).
• Grouping C CogSport, Trails A and B, and Digit
  Symbol (computerized).
• ABC, ACB, BAC BCA, CAB, CBA.

48
Cross-Validation Example ImPACT CRT
49
Cross-Validation Example CogSport CRT
50
Cross-Validation Example CRI CRT
Cued Reaction Time Press the spacebar as quickly
as possible only when a white circle immediately
follows the presentation of a black square.
51
Cross-Validation of Computer-Based Measures - SRT
Results
52
Cross-Validation of Computer-Based Measures - CRT
Results
53
Cross-Validation of Computer-Based Measures -
Processing Speed Results
54
Cross-Validation of Computer-Based Measures -
Memory Results
55
Cross-Validation of Computer-Based Measures -
Implications

• These tests share some common variance on
  constructs such as processing speed and reaction
  time, but not within the domain of memory.
• The Processing Speed Indices/measures (ImPACT,
  HeadMinder, Trails B and Digit Symbol) correlated
  the most consistently.
• Baseline evaluations using one measure can not be
  used as a basis for post-concussion assessment
  using another measure.

56
Cross-Validation of Computer-Based Measures -
Limitations

• Small sample size.
• Reliance on univariate correlations.
• Subjects assessed independently.
• No concussed subjects.
• Not comparing tests sensitivity to effects of
  concussion.

57
MeanwhileConcussion Effects on Youth Athletes?

• Relying on symptoms alone may be dangerous
• Attentional processes, memory, and cognitive
• speed are key elements of testing
• Younger athletes deserve particular attention

58
Prolonged Effects of Concussion?(Schatz
McNamara ACN 2001 Abstract)

• Self-reported history of concussion
• 56 college freshmen, ages 17-19
• Divided into independent groups on the basis of
  concussion history
• 19 with one or more previous concussion,
• 39 with self-reported history of no previous
  concussions.

59
Prolonged Effects of Concussion?(Schatz
McNamara ACN 2001 Abstract)
Mild, enduring effects of cerebral concussion can
be identified in otherwise healthy college
freshmen with a history of concussion.These
enduring effects of previous cerebral concussions
appear to involve attentional processes, and
warrant further investigation.
60
Prolonged Effects of Concussion?(Moser Schatz
ACN 2001 Moser, Schatz, Jordan, Neurosurgery
2005)

• Youth Athletes from a college-prep boarding
  school (Ivy-bound)
• Mandatory participation in sports
• Multiple sports over 5-10 years
• No concussion program in place
• Attempt to understand/replicate

61
Dependent Measure RBANS

• Subtests measure multiple neurocognitive domains
• Immediate MemoryList Memory - recall of 10 words
  presented orally.
• Story Memory - recall of short story presented
  orally.
• Visuospatial/Contructional
• Figure Copy - Copy of multi-part geometric
  drawing.
• Line Orientation - identify lines from a
  drawing.
• Language
• Picture Naming - Naming of pictures of objects.
• Semantic Fluency - Name examples from category
  in one minute.
• Attention
• Digit Span - Repeat a string of digits presented
  orally.
• Coding - Matches geometric shapes corresponding
  to numbers.
• Delayed Memory
• List Recall - Recall 10 words learned in the
  List Learning subtest.
• List Recognition - recognition of 20 words
  presented orally.
• Story Memory - Recall of short story learned
  earlier.

62
Prolonged Effects Pilot Study (Moser Schatz,
Arch Clinical Neuropsych 2001)

• Youth athlete volunteers, divided into
  independent groups
• on the basis of concussion history.
• Zero or One Previous Concussion 8 healthy
  volunteers with either no history of concussion,
  or had sustained one previous concussion (not
  within the past six months).
• Two Previous Concussions 13 youth athletes who
  had sustained two or more previous concussions
  (not within the past six months).
• Recent Concussion 13 youth athletes who had
  sustained a recent concussion, with no
  identified medical or neuropsychological
  difficulties related to concussion one week
  after testing.

63
Prolonged Effects Pilot Results
64
Follow-up Study(Moser, Schatz Jordan,
Neurosurgery 2005)

• 238 youth athlete volunteers ... divided into
  four independent
• groups on the basis of concussion history.
• No Concussion 82 healthy volunteers with no
  history of concussion.
• One Previous Concussion 56 youth athletes who
  had sustained one previous concussion (not
  within the past six months).
• Two Previous Concussions 51 youth athletes who
  had sustained two or more previous concussions
  (not within the past six months).
• Recent Concussion 49 youth athletes who had
  sustained a recent concussion, with no
  identified medical or neuropsychological
  difficulties related to concussion within one
  week of testing.

65
Prolonged Effects-GPA
66
Prolonged Effects-RBANS
67
Prolonged Effects Results

• Multivariate Analysis of Variance (MANOVA)
  revealed a significant overall effect of
  concussion history on cognition F(21,672)1.8
  p.015.
• Univariate F-tests revealed significant main
  effects of concussion history on Attention
  F(3,228)4.72 p.003 and GPA F(3,228 5.76
  p.001.

68
Prolonged Effects in Youth Athletes

• Health non-concussed youth athletes with a
  history of concussion often show subtle deficits
  in attention and concentration at baseline
  assessment.
• These enduring effects of previous cerebral
  concussions can be detected using traditional
  measures.
• Concussions appear to occur in female athletes
  at a greater rate/frequency.

69
Youth Athletes What we think we know

• Contributing to these findings
• A more vulnerable and susceptible youth brain
• Participation in multiple sports over a long
  period of years.

70

• Emotionality
• Feeling more emotional
• Sadness
• Nervousness
• Irritability

• Somatic Symptoms
• Visual Problems
• Dizziness
• Balance Difficulties
• Headaches
• Light Sensitivity
• Nausea

• Cognitive Symptoms
• Attention Problems
• Memory dysfunction
• Fogginess
• Fatigue
• Cognitive slowing

• Sleep Disturbance
• Difficulty falling asleep
• Sleeping less than usual

Factor Analysis, Post-Concussion Symptom
Scale N327, High School,Univ Athletes Within 7
Days of Concussion (Pardini et al, 2004)
71
Post-Concussion Gender DifferencesCovassin,
Schatz, Swanik, Neurosurgery, 2007)

• 79 NCAA Division 1 Athletes
• Completed ImPACT at baseline
• Sustained concussion warranting serial
  assessment up to 10 days post-concussion
• Average 3, 8 days post-concussion
• Males (N41) Baseball, cheerleading, football,
  ice hockey, lacrosse, soccer, volleyball, and
  wrestling
• Females (N38) basketball, cheerleading,
  gymnastics, lacrosse, soccer, softball,
  volleyball,

72
Post-Concussion Gender DifferencesCovassin,
Schatz, Swanik, Neurosurgery, 2007)

• Baseline No Gender differences F(5,73).80
  P0.55
• Post-Concussion 3x2 mixed-factoral design MANOVA
• Time (Baseline, 3 days, 8 days) F(2,76)1670
  P0.0001 ES.98
• Gender F(1, 77).16 p.69 ES.002
• Time x Gender Interaction F(2,76).54 p.59,
  ES.01

73
Post-Concussion Gender DifferencesCovassin,
Schatz, Swanik, Neurosurgery, 2007)

• Post-Concussion Symptoms
• Male athletes reported significantly higher
  symptom scores for
• Sadness F(1,77)13.05, P0.001
• Vomiting F(1,77) 5.95, P0.017

74
Post-Concussion Gender DifferencesCovassin,
Schatz, Swanik, Neurosurgery, 2007)

• Reliable Change Indices (RCI)
• At Time 1 (up to 3 days post-injury)
• 58 of participants had one or more reliable
  declines in performance or increases in symptom
  reporting
• At Time 2 (up to 10 days post-injury)
• 30 of participants were still showing one or
  more reliable changes from pre-season levels.

75
NEW MANAGEMENT STRATEGIESCIS Group, Vienna
(2001), Prague (2004)

• Removal of symptomatic athletes from play
• Graduated return to play
• Neuropsychological testing recommended
• One of the Cornerstones of Management

Aubry, Cantu, Dvorak, Graf-Baumann, Johnston,
Kelly, Lovell, McCrory, Meeuwise, Schasmasch,
2001. Clinical J. Sports Med.
76
Current Large-Scale Programs Neuropsychological
Testing

• 20 NFL Teams
• IRL, F1, CHAMP Car
• NASCAR
• USA Olympic Hockey
• USA Hockey
• 400 High Schools in US
• 60 Sports Medicine Clinics in US
• Pro Boxing in California
• USA Ski Team
• USA Soccer Juniors

• Ontario Hockey League
• New Zealand Rugby
• S. African Rugby
• World Cup Soccer
• 150 Universities in US
• Many Neuropsychology Clinics in US
• Major League Baseball
• Major League Baseball Umpires

77
WHY USE NEUROPSYCHOLOGICAL TESTING? Unique
Contribution To The Diagnostic Puzzle

• Testing Provides Unique Information
• Concussed Athletes Often Deny Symptoms
• Athletes May Lack Awareness of Symptoms

78
UNIQUE CONTRIBUTION OF NEUROPSYCHOLOGICAL
TESTINGTO CONCUSSION MANAGEMENT
Testing reveals cognitive deficits in
asymptomatic athletes within 4 days post-injury
N215, MANOVA plt.000000
79
UNIQUE CONTRIBUTION OF NEUROPSYCHOLOGICAL
TESTINGTO CONCUSSION MANAGEMENT
Reaction Time Processing Speed
MANOVA plt.000000 (ImPACT Test Battery)
80
VALUE ADDED OF NEUROPSYCHOLOGICAL TESTING
NP testing increases Diagnostic yield to 88
Either
Neuropsych
Symptoms
declined From baseline
201 concussed High School and collegiate athletes
tested with 2 days of injury. Abnormal
performance determined by RCIs (van Kampen,
2004).
81
WHY USE NEUROPSYCHOLOGICAL TESTING? Mild or
Ding Injuries May be Significant

• Cannot gauge severity of injury based on initial
  symptoms
• Acute recovery may not be a linear process

82
Concussion and Memory Dysfunction

• 64 high school athletes with Grade 1 concussion
• 24 Non-injured control subjects
• All athletes diagnosed with ding
• Confusion, amnesia, signs/symptoms cleared
• within 15 minutes
• No athlete in sample sustained LOC
• No athlete returned to contest
• ImPACT evaluation obtained at baseline, 36
  hours,
• 4 days and 7 days post-concussion

Lovell et al., J. Neurosurgery, 2003.
83
Memory Impairment Following Mild Concussion
Time of Evaluation
Lovell, Collins, Iverson et al., J. Neurosurgery,
98, 2003
84
Summary

• Current research supports the use of
  neuropsychological testing following
  concussion
• Relying on symptoms alone may be dangerous
• Attentional processes, memory, and cognitive
• speed are key elements of testing
• Younger athletes deserve particular attention

85
And Now for Something Completely Different

• Effort (Green, et al., Brain Injury, 2001)
• gt50 of variance in scores was due to poor
  effort
• Education 11
• Age 4
• Symptom Validity Testing (Bush, et al NAN, ACN),
• it is necessary to evaluate symptom validity
  objectively in any neuropsychological assessment

86
And Now for Something Completely Different

• Daubert v. Merrell Dow Pharmaceuticals (1993)
  held that trial judges should permit expert
  scientific testimony only when the reasoning or
  methodology underlying the testimony is
  scientifically valid, and properly can be
  applied to the facts in issue.

87
And Now for Something Completely Different

• Effort Tests
• Rey 15-item, Dot Counting
• Test of Memory Malingering (TOMM)
• Word Memory Test (WMT)
• CARB (Comp. Assess. Response Bias)
• Validity Indicator Profile (VIP)
• MMPI-2

88
Assessment of Effort - Rationale (Schatz
Sucharski, in some stage of submission)

• Little data on effort at time of assessment
• speculation that athletes are often motivated
  to underreport symptoms so they can return to
  competition (Echemendia Cantu, 2003)
• motivated to underreport subjective symptoms to
  hasten the return to competition. (Erlanger, et
  al., 2003)
• An athletes apparent fear of removal from a
  game or of losing his or her position on the team
  may tempt some athletes to deny or underreport
  postconcussive symptoms. (Lovell, 1998)
• Ostensibly, symptom minimization occurs in
  hopes of a faster return to the playing field,
  court or ice. (Lovell, et al., 2002)
• it is more likely that suspicion regarding the
  use of the test results and/or general
  disinterest and apathy could impact the accurate
  measurement of cognitive ability at baseline
  (Echemendia Cantu, 2003)

89
Assessment of Effort - Rationale

• Bailey, Echemendia, Arnett (2006), JINS
• Assigned to High Motivation at Baseline (HMB) and
  Suspect Motivation at Baseline (SMB) groups based
  on whether baseline performance fell one or more
  standard deviations from the mean of the given
  measure
• N26 to 33, Pre, Post-Mild TBI, Trails, Dig Span,
  Stroop
• In repeated measures ANCOVA (that removed
  achievement performance), the SMB groups
  demonstrated greater improvement than the HMB
  groups for the Trail Making Test A B ( TMT-A
  B), Digit Span, and Stroop-Color Word (Stroop-CW)
  tests.

90
Assessment of Effort - Methodology

• 155 Participants 77 athletes, 78 from human
  subjects pool
• Administered Word Memory Test (WMT) and ImPACT
• Only looked at Baseline performance

91
Assessment of Effort - Methodology

• Word Memory Test (WMT)
• Show word pairs (e.g., Boy-Girl)
• Show cue word (e.g., Boy)
• Show target choices (e.g., Girl, Truck)TBI
  Patients 95

92
Assessment of Effort - Incidence

• Incidence of Poor Effort

93
Assessment of Effort - Effects
94
Validation of MilliSecond Accuracy in
MicroComputers (unpublished data)
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95
Validation of MilliSecond Accuracy in
MicroComputers (unpublished data)
96
Validation of MilliSecond Accuracy in
MicroComputers
97
Validation of MilliSecond Accuracy in
MicroComputers
98
Validation of MilliSecond Accuracy in
MicroComputers
99
Validation of MilliSecond Accuracy in
MicroComputers
100
Millisecond Accuracy?

• Baseline to post-concussion computers
• Caution when interpreting reaction time and
  processing speed
• Use of software by clinicians

101
Assessment of Effort - Implications

• Given the wide-spread use of computer-based tests
  for the purpose of documenting baseline cognitive
  function in athletes, neuro-psychologists and
  sports-medicine professionals should utilize
  external measures of athletes' effort.
• Further, employing normal controls from human
  subjects pools may provide less accurate
  comparisons than desired.

102
What we need to know more about

• Diagnosing and managing concussions with
  computer-based measures
• Ongoing, external validation of existing measures
• Ongoing validation of computer-based measures in
  prospective clinical samples
• Accurate standard for timing accuracy

103
What we need to know more about

• Diagnosing and managing concussions in youth
  athletes
• Junior High, Grade School, Youth Leagues
• JV, Club Sports
• Gender

104
What we NEED

• Baseline screenings for all athletes, but
  especially in vulnerable youth athletes.
• -documenting pre-concussion status,
• -pre and post concussion comparisons -multiple
  sliding baseline.
• Public service announcements
• Involvement /awareness of pediatricians and
  family practices Neuropychology