human
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background Neurocognitive testing has been endorsed as a “ cornerstone ’ of concussion management by recent Vienna and Prague meetings of the Concussion in Sport Group . Neurocognitive testing is important given the potential unreliability of athlete self-report after injury . Relying only on athletes'ormalities after injury . Study Design Case control study ; Level of evidence , 3 . Methods High school and college athletes with a diagnosed concussion were tested 2 days after injury . Postinjury neurocognitive performance ( Immediate Postconcussion Assessment and Cognitive Testing ) and symptom ( postconcussion symptom ) scores were compared with preinjury ( baseline ) scores and with those of an agex and education-matched noninjured athlete control group . “ Abnormal ” test performance was determined statistically with Reliable Change Index scores . Results Sixty-four percent of concussed athletes reported a significant increase in symptoms , as judged by postconcussion symptom scores , compared with preinjury baseline at 2 days after injury . Eighty-three percent of the concussed sample demonstrated significantly poorer neurocognitive test results relative to their own baseline performance . The addition of neurocognitive testing result ed in a net increase in sensitivity of 19 % . Ninety-three percent of the sample had either abnormal neurocognitive test results or a significant increase in symptoms , relative to their own baseline ; 30 % of a control group demonstrated either abnormalities in neurocognitive testing or elevated symptoms , as judged by postconcussion symptom scores . For the concussed group , use of symptom and neurocognitive test results result ed in an increased yield of 29 % overreliance on symptoms alone . In contrast , 0 % of the control group had both symptoms and abnormal neurocognitive testing . Conclusion Reliance on patients ’ self-reported symptoms after concussion is likely to result in underdiagnosis of concussion and may result in premature return to play . Neurocognitive testing increases diagnostic accuracy when used in conjunction with self-reported symptoms OBJECT The aim of this study was to develop a decision rule for physicians in developing countries to identify patients with minor head injury who will benefit from emergency brain CT scanning .  METHODS Three hundred eighteen patients with a history of blunt head trauma and a Glasgow Coma Scale ( GCS ) score > or= 13 who had presented within 12 hours of trauma underwent nonenhanced brain CT and were included in this prospect i ve study . Computed tomography findings that necessitated neurosurgical care ( either observation or intervention ) were considered as positive findings . Logistic regression was used to develop the decision rule . RESULTS Computed tomography scans  were always normal in patients < 65 years old who did not have an obvious head wound , a raccoon sign , vomiting , memory deficit , or a decrease in their GCS score .  Patients with 1 major criterion ( GCS score < 14 , raccoon sign , failure to remember the impact , age > 65 years , or vomiting ) or 2 minor criteria ( wound at the scalp or GCS score < 15 ) had an abnormal CT scan in 13 % of the cases . CONCLUSIONS The decision rule developed by the authors appears to be 100 % sensitive and 46 % specific for positive findings on brain CT and will , in developing countries , help clarify the decision to obtain scans OBJECTIVE : The purpose of this study was to compare concussion rates and recovery times for athletes wearing newer helmet technology compared to traditional helmet design . METHODS : This was a three-year , prospect i ve , naturalistic , cohort study . Participants were 2,141 high school athletes from Western Pennsylvania . Approximately half of the sample wore the Revolution helmet manufactured by Riddell , Inc.  ( n = 1,173 ) and the remainder of the sample used  st and ard helmets ( n = 968 ) . Athletes underwent computerized neurocognitive testing through the use of ImPACT at the beginning of the study . Following a concussion , players were reevaluated at various time intervals until recovery was complete . RESULTS : In the total sample , the concussion rate in athletes wearing the Revolution was 5.3 % and in athletes wearing st and ard helmets was 7.6 % [ & khgr;2 ( 1 , 2 , 141 ) = 4.96 , P < 0.027 ] . The relative risk estimate was 0.69 ( 95 % confidence interval = 0.499– 0.958 ) . Wearing the Revolution helmet was associated with approximately a 31 % decreased relative risk and 2.3 % decreased absolute risk for sustaining a concussion in this cohort study . The athletes wearing the Revolution did not differ from athletes wearing st and ard helmets on the mechanism of injury ( e.g. , head-to-head strike ) , on-field concussion markers ( e.g. , amnesia or loss of consciousness ) , or on-field presentation of symptoms ( e.g. , headaches , dizziness , or balance problems ) . CONCLUSION : Recent sophisticated laboratory research has better eluci date d injury biomechanics associated with concussion in professional football players . This data has led to changes in helmet design and new helmet technology , which appears to have beneficial effects in reducing the incidence of cerebral concussion in high school football players OBJECTIVE Our purpose was to determine whether sex differences exist with respect to post-concussion symptoms and neurocognitive function in concussed collegiate athletes . METHODS A prospect i ve dependent- sample cohort design was used to compare baseline and post-concussion neuropsychological test scores and endorsed symptoms as functions of serial post-concussion assessment with respect to time and sex . The Immediate Post-concussion Assessment and Cognitive Testing ( ImPACT ) battery was administered to a multicenter analysis group of 79 concussed athletes . This computerized neuropsychological test was given to the athletes during the preseason and , on average , 2 and 8 days postinjury . RESULTS Multivariate analyses revealed no significant between-group differences on baseline test performance with respect to sex on any of the ImPACT composite scores or on the total symptom score . Multivariate analyses of post-concussion data revealed a significant main effect of time on ImPACT scores , but no main effect of sex was identified , and no time-by-sex interaction existed . Post hoc analysis revealed that concussed female athletes performed significantly worse than concussed male athletes on visual memory tasks ( P = 0.001 ) , and analysis of endorsed post-concussion symptoms revealed that concussed men were significantly more likely than concussed women to report post-concussion symptoms of vomiting ( P = 0.001 ) and sadness ( P = 0.017 ) . Athletes ' scores were examined individually using the reliable-change methodology . At 2 days post-injury , 58 % of concussed athletes had one or more reliable incidents of performance decline or increases in symptom reporting . At 8 days post-concussion , 30 % of concussed athletes were still showing one or more reliable change from preseason values . CONCLUSIONS College athletes exhibit differences on visual memory composite scores and symptoms post-concussion as a function of sex . These data support the importance of evaluating neuropsychological status and post-concussion symptoms in concussed athletes . In addition , these data illustrate the importance of analyzing an individual athlete 's recovery pattern , because individual differences in recovery trajectories may be overshadowed by global norm-group comparisons The purpose of the current study was to explore potential differences in pre- and post-concussion performance on a computerized neurocognitive concussion test between African American and White high-school and collegiate student-athletes . A prospect i ve case-control design was used to compare baseline and 2- and 7-day post-concussion computerized neurocognitive performance and symptoms between 48 White and 48 African American athletes matched for age , gender , and concussion history . The Immediate Post-Concussion Assessment Cognitive Test ( ImPACT ) version 2.0 ( NeuroHealth System , LLC , Pittsburgh , PA , USA ) computer software program was used to assess neurocognitive function ( i.e. , verbal and visual memory , motor processing speed , and reaction time ) and concussion symptoms . Regardless of race/ethnicity , there were significant decrements in computerized neurocognitive performance and increased symptoms following a concussion for the entire sample . African Americans and Whites did not differ significantly on baseline or post-concussion verbal memory , visual memory , reaction time , and total reported symptoms . However , African American participants were 2.4 × more likely to have at least one clinical ly significant cognitive decline on ImPACT at 7 days post-concussion and scored lower at 7 days post-concussion compared with baseline on processing speed than White participants . The authors concluded that the baseline ImPACT test was culturally equivalent and construct valid for use with these two racial/ethnic groups . However , in contrast , the findings support deleterious performance for the African American athletes compared with the White athletes on the ImPACT post-concussion evaluation that is of critical clinical relevance and warrants further research OBJECTIVE The relationship between athlete reports of symptoms , neurophysiological activation , and neuropsychological functioning is investigated in a sample of high school athletes . METHODS All athletes were evaluated using functional magnetic resonance imaging ( fMRI ) , a computer-based battery of neurocognitive tests , and a subjective symptom scale . Athletes were evaluated within approximately 1 week of injury and again after clinical recovery using all assessment modalities . RESULTS This study found that abnormal fMRI results during the first week of recovery predicted clinical recovery . As a group , athletes who demonstrated hyperactivation on fMRI scans at the time of their first fMRI scan demonstrated a more prolonged clinical recovery than athletes who did not demonstrate hyperactivation at the time of their first fMRI scan . CONCLUSION These results demonstrate the relationship between neurophysiological , neuropsychological , and subjective symptom data in a relatively large sample composed primarily of concussed high school athletes .  fMRI represents an important evolving technology for the underst and ing of brain recovery after concussion and may help shape return-to-play guidelines in the future BACKGROUND : This study compared early serum levels of ubiquitin C-terminal hydrolase ( UCH-L1 ) from patients with mild and moderate traumatic brain injury ( TBI ) with uninjured and injured controls and examined their association with traumatic intracranial lesions on computed tomography ( CT ) scan ( CT positive ) and the need for neurosurgical intervention ( NSI ) . METHODS : This prospect i ve cohort study enrolled adult patients presenting to three tertiary care Level I trauma centers after blunt head trauma with loss of consciousness , amnesia , or disorientation and a Glasgow Coma Scale ( GCS ) score 9 to 15 . Control groups included normal uninjured controls and nonhead injured trauma controls presenting to the emergency department with orthopedic injuries or motor vehicle crash without TBI . Blood sample s were obtained in all trauma patients within 4 hours of injury and measured by enzyme-linked immunosorbent assay for UCH-L1 ( ng/mL ± st and ard error of the mean ) . RESULTS : There were 295 patients enrolled , 96 TBI patients ( 86 with GCS score 13–15 and 10 with GCS score 9–12 ) , and 199 controls ( 176 uninjured , 16 motor vehicle crash controls , and 7 orthopedic controls ) . The AUC for distinguishing TBI from uninjured controls was 0.87 ( 95 % confidence interval [ CI ] , 0.82–0.92 ) and for distinguishing those TBIs with GCS score 15 from controls was AUC 0.87 ( 95 % CI , 0.81–0.93 ) . Mean UCH-L1 levels in patients with CT negative versus CT positive were 0.620 ( ±0.254 ) and 1.618 ( ±0.474 ) , respectively ( p < 0.001 ) , and the AUC was 0.73 ( 95 % CI , 0.62–0.84 ) . For patients without and with NSI , levels were 0.627 ( 0.218 ) versus 2.568 ( 0.854 ; p < 0.001 ) , and the AUC was 0.85 ( 95 % CI , 0.76–0.94 ) . CONCLUSION : UCH-L1 is detectable in serum within an hour of injury and is associated with measures of injury severity including the GCS score , CT lesions , and NSI . Further study is required to vali date these findings before clinical application . LEVEL OF EVIDENCE : II , prognostic study Previous studies have presented conflicting results regarding the predictive value of various clinical symptoms and signs for performing computed tomography ( CT ) scan in minor head injury . Moreover , despite the presence in the literature of several similar publications regarding whether or not CT should be employed at the time of presentation of minor head injured patients , data regarding delayed CT are limited . The objective of this study was to determine whether high-risk criteria represent a significant indication for initial CT scan in patients with minor head trauma , and whether or not analysis using delayed CT scan is necessary in patients with high-risk criteria before being discharged . Patients presenting to the Emergency Department with minor head trauma between September 1 , 2003 and September 1 , 2004 were evaluated prospect ively . After being divided into two main groups , low- and high-risk , four separate sub-groups based on age were established . Initial spiral CT examination was done within 3 h of trauma on all patients in addition to a delayed control CT scan in those with high-risk criteria between 16 and 24 h after trauma . The difference between the high- and low-risk groups in terms of abnormal CT findings was statistically significant ( p < 0.0005 ) . Among high-risk patients there was a significant 
    Output:
    
agent
: The results of this systematic review identify the consistent and prevalent indicators of concussion and their associations , derived from the strongest evidence in the published literature .
***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background Neurocognitive testing has been endorsed as a “ cornerstone ’ of concussion management by recent Vienna and Prague meetings of the Concussion in Sport Group . Neurocognitive testing is important given the potential unreliability of athlete self-report after injury . Relying only on athletes'ormalities after injury . Study Design Case control study ; Level of evidence , 3 . Methods High school and college athletes with a diagnosed concussion were tested 2 days after injury . Postinjury neurocognitive performance ( Immediate Postconcussion Assessment and Cognitive Testing ) and symptom ( postconcussion symptom ) scores were compared with preinjury ( baseline ) scores and with those of an agex and education-matched noninjured athlete control group . “ Abnormal ” test performance was determined statistically with Reliable Change Index scores . Results Sixty-four percent of concussed athletes reported a significant increase in symptoms , as judged by postconcussion symptom scores , compared with preinjury baseline at 2 days after injury . Eighty-three percent of the concussed sample demonstrated significantly poorer neurocognitive test results relative to their own baseline performance . The addition of neurocognitive testing result ed in a net increase in sensitivity of 19 % . Ninety-three percent of the sample had either abnormal neurocognitive test results or a significant increase in symptoms , relative to their own baseline ; 30 % of a control group demonstrated either abnormalities in neurocognitive testing or elevated symptoms , as judged by postconcussion symptom scores . For the concussed group , use of symptom and neurocognitive test results result ed in an increased yield of 29 % overreliance on symptoms alone . In contrast , 0 % of the control group had both symptoms and abnormal neurocognitive testing . Conclusion Reliance on patients ’ self-reported symptoms after concussion is likely to result in underdiagnosis of concussion and may result in premature return to play . Neurocognitive testing increases diagnostic accuracy when used in conjunction with self-reported symptoms OBJECT The aim of this study was to develop a decision rule for physicians in developing countries to identify patients with minor head injury who will benefit from emergency brain CT scanning .  METHODS Three hundred eighteen patients with a history of blunt head trauma and a Glasgow Coma Scale ( GCS ) score > or= 13 who had presented within 12 hours of trauma underwent nonenhanced brain CT and were included in this prospect i ve study . Computed tomography findings that necessitated neurosurgical care ( either observation or intervention ) were considered as positive findings . Logistic regression was used to develop the decision rule . RESULTS Computed tomography scans  were always normal in patients < 65 years old who did not have an obvious head wound , a raccoon sign , vomiting , memory deficit , or a decrease in their GCS score .  Patients with 1 major criterion ( GCS score < 14 , raccoon sign , failure to remember the impact , age > 65 years , or vomiting ) or 2 minor criteria ( wound at the scalp or GCS score < 15 ) had an abnormal CT scan in 13 % of the cases . CONCLUSIONS The decision rule developed by the authors appears to be 100 % sensitive and 46 % specific for positive findings on brain CT and will , in developing countries , help clarify the decision to obtain scans OBJECTIVE : The purpose of this study was to compare concussion rates and recovery times for athletes wearing newer helmet technology compared to traditional helmet design . METHODS : This was a three-year , prospect i ve , naturalistic , cohort study . Participants were 2,141 high school athletes from Western Pennsylvania . Approximately half of the sample wore the Revolution helmet manufactured by Riddell , Inc.  ( n = 1,173 ) and the remainder of the sample used  st and ard helmets ( n = 968 ) . Athletes underwent computerized neurocognitive testing through the use of ImPACT at the beginning of the study . Following a concussion , players were reevaluated at various time intervals until recovery was complete . RESULTS : In the total sample , the concussion rate in athletes wearing the Revolution was 5.3 % and in athletes wearing st and ard helmets was 7.6 % [ & khgr;2 ( 1 , 2 , 141 ) = 4.96 , P < 0.027 ] . The relative risk estimate was 0.69 ( 95 % confidence interval = 0.499– 0.958 ) . Wearing the Revolution helmet was associated with approximately a 31 % decreased relative risk and 2.3 % decreased absolute risk for sustaining a concussion in this cohort study . The athletes wearing the Revolution did not differ from athletes wearing st and ard helmets on the mechanism of injury ( e.g. , head-to-head strike ) , on-field concussion markers ( e.g. , amnesia or loss of consciousness ) , or on-field presentation of symptoms ( e.g. , headaches , dizziness , or balance problems ) . CONCLUSION : Recent sophisticated laboratory research has better eluci date d injury biomechanics associated with concussion in professional football players . This data has led to changes in helmet design and new helmet technology , which appears to have beneficial effects in reducing the incidence of cerebral concussion in high school football players OBJECTIVE Our purpose was to determine whether sex differences exist with respect to post-concussion symptoms and neurocognitive function in concussed collegiate athletes . METHODS A prospect i ve dependent- sample cohort design was used to compare baseline and post-concussion neuropsychological test scores and endorsed symptoms as functions of serial post-concussion assessment with respect to time and sex . The Immediate Post-concussion Assessment and Cognitive Testing ( ImPACT ) battery was administered to a multicenter analysis group of 79 concussed athletes . This computerized neuropsychological test was given to the athletes during the preseason and , on average , 2 and 8 days postinjury . RESULTS Multivariate analyses revealed no significant between-group differences on baseline test performance with respect to sex on any of the ImPACT composite scores or on the total symptom score . Multivariate analyses of post-concussion data revealed a significant main effect of time on ImPACT scores , but no main effect of sex was identified , and no time-by-sex interaction existed . Post hoc analysis revealed that concussed female athletes performed significantly worse than concussed male athletes on visual memory tasks ( P = 0.001 ) , and analysis of endorsed post-concussion symptoms revealed that concussed men were significantly more likely than concussed women to report post-concussion symptoms of vomiting ( P = 0.001 ) and sadness ( P = 0.017 ) . Athletes ' scores were examined individually using the reliable-change methodology . At 2 days post-injury , 58 % of concussed athletes had one or more reliable incidents of performance decline or increases in symptom reporting . At 8 days post-concussion , 30 % of concussed athletes were still showing one or more reliable change from preseason values . CONCLUSIONS College athletes exhibit differences on visual memory composite scores and symptoms post-concussion as a function of sex . These data support the importance of evaluating neuropsychological status and post-concussion symptoms in concussed athletes . In addition , these data illustrate the importance of analyzing an individual athlete 's recovery pattern , because individual differences in recovery trajectories may be overshadowed by global norm-group comparisons The purpose of the current study was to explore potential differences in pre- and post-concussion performance on a computerized neurocognitive concussion test between African American and White high-school and collegiate student-athletes . A prospect i ve case-control design was used to compare baseline and 2- and 7-day post-concussion computerized neurocognitive performance and symptoms between 48 White and 48 African American athletes matched for age , gender , and concussion history . The Immediate Post-Concussion Assessment Cognitive Test ( ImPACT ) version 2.0 ( NeuroHealth System , LLC , Pittsburgh , PA , USA ) computer software program was used to assess neurocognitive function ( i.e. , verbal and visual memory , motor processing speed , and reaction time ) and concussion symptoms . Regardless of race/ethnicity , there were significant decrements in computerized neurocognitive performance and increased symptoms following a concussion for the entire sample . African Americans and Whites did not differ significantly on baseline or post-concussion verbal memory , visual memory , reaction time , and total reported symptoms . However , African American participants were 2.4 × more likely to have at least one clinical ly significant cognitive decline on ImPACT at 7 days post-concussion and scored lower at 7 days post-concussion compared with baseline on processing speed than White participants . The authors concluded that the baseline ImPACT test was culturally equivalent and construct valid for use with these two racial/ethnic groups . However , in contrast , the findings support deleterious performance for the African American athletes compared with the White athletes on the ImPACT post-concussion evaluation that is of critical clinical relevance and warrants further research OBJECTIVE The relationship between athlete reports of symptoms , neurophysiological activation , and neuropsychological functioning is investigated in a sample of high school athletes . METHODS All athletes were evaluated using functional magnetic resonance imaging ( fMRI ) , a computer-based battery of neurocognitive tests , and a subjective symptom scale . Athletes were evaluated within approximately 1 week of injury and again after clinical recovery using all assessment modalities . RESULTS This study found that abnormal fMRI results during the first week of recovery predicted clinical recovery . As a group , athletes who demonstrated hyperactivation on fMRI scans at the time of their first fMRI scan demonstrated a more prolonged clinical recovery than athletes who did not demonstrate hyperactivation at the time of their first fMRI scan . CONCLUSION These results demonstrate the relationship between neurophysiological , neuropsychological , and subjective symptom data in a relatively large sample composed primarily of concussed high school athletes .  fMRI represents an important evolving technology for the underst and ing of brain recovery after concussion and may help shape return-to-play guidelines in the future BACKGROUND : This study compared early serum levels of ubiquitin C-terminal hydrolase ( UCH-L1 ) from patients with mild and moderate traumatic brain injury ( TBI ) with uninjured and injured controls and examined their association with traumatic intracranial lesions on computed tomography ( CT ) scan ( CT positive ) and the need for neurosurgical intervention ( NSI ) . METHODS : This prospect i ve cohort study enrolled adult patients presenting to three tertiary care Level I trauma centers after blunt head trauma with loss of consciousness , amnesia , or disorientation and a Glasgow Coma Scale ( GCS ) score 9 to 15 . Control groups included normal uninjured controls and nonhead injured trauma controls presenting to the emergency department with orthopedic injuries or motor vehicle crash without TBI . Blood sample s were obtained in all trauma patients within 4 hours of injury and measured by enzyme-linked immunosorbent assay for UCH-L1 ( ng/mL ± st and ard error of the mean ) . RESULTS : There were 295 patients enrolled , 96 TBI patients ( 86 with GCS score 13–15 and 10 with GCS score 9–12 ) , and 199 controls ( 176 uninjured , 16 motor vehicle crash controls , and 7 orthopedic controls ) . The AUC for distinguishing TBI from uninjured controls was 0.87 ( 95 % confidence interval [ CI ] , 0.82–0.92 ) and for distinguishing those TBIs with GCS score 15 from controls was AUC 0.87 ( 95 % CI , 0.81–0.93 ) . Mean UCH-L1 levels in patients with CT negative versus CT positive were 0.620 ( ±0.254 ) and 1.618 ( ±0.474 ) , respectively ( p < 0.001 ) , and the AUC was 0.73 ( 95 % CI , 0.62–0.84 ) . For patients without and with NSI , levels were 0.627 ( 0.218 ) versus 2.568 ( 0.854 ; p < 0.001 ) , and the AUC was 0.85 ( 95 % CI , 0.76–0.94 ) . CONCLUSION : UCH-L1 is detectable in serum within an hour of injury and is associated with measures of injury severity including the GCS score , CT lesions , and NSI . Further study is required to vali date these findings before clinical application . LEVEL OF EVIDENCE : II , prognostic study Previous studies have presented conflicting results regarding the predictive value of various clinical symptoms and signs for performing computed tomography ( CT ) scan in minor head injury . Moreover , despite the presence in the literature of several similar publications regarding whether or not CT should be employed at the time of presentation of minor head injured patients , data regarding delayed CT are limited . The objective of this study was to determine whether high-risk criteria represent a significant indication for initial CT scan in patients with minor head trauma , and whether or not analysis using delayed CT scan is necessary in patients with high-risk criteria before being discharged . Patients presenting to the Emergency Department with minor head trauma between September 1 , 2003 and September 1 , 2004 were evaluated prospect ively . After being divided into two main groups , low- and high-risk , four separate sub-groups based on age were established . Initial spiral CT examination was done within 3 h of trauma on all patients in addition to a delayed control CT scan in those with high-risk criteria between 16 and 24 h after trauma . The difference between the high- and low-risk groups in terms of abnormal CT findings was statistically significant ( p < 0.0005 ) . Among high-risk patients there was a significant 
    Output:
    