title: Systematic review of the prognosis after mild traumatic brain injury in adults: cognitive, psychiatric, and mortality outcomes: results of the International Collaboration on Mild Traumatic Brain Injury Prognosis.
abstract: OBJECTIVE
  To synthesize the best available evidence on objective outcomes after adult mild traumatic brain injury (MTBI).
  
  
  METHODS
  MEDLINE and other databases were searched (2001-2012) for studies related to MTBI. Inclusion criteria included published, peer-reviewed articles in English and other languages. References were also identified from the bibliographies of eligible articles.
  
  
  METHODS
  Randomized controlled trials and cohort and case-control studies were selected according to predefined criteria. Studies had to have a minimum of 30 MTBI cases and assess objective outcomes in adults.
  
  
  METHODS
  Eligible studies were critically appraised using a modification of the Scottish Intercollegiate Guidelines Network (SIGN) criteria. Two reviewers independently reviewed each study and extracted data from accepted articles into evidence tables.
  
  
  RESULTS
  Evidence was synthesized qualitatively according to modified SIGN criteria, and studies were categorized as exploratory or confirmatory based on the strength of their design and evidence. After 77,914 records were screened, 299 were found to be relevant and critically reviewed, and 101 were deemed scientifically admissible. Of these, 21 studies that were related to the objective outcomes form the basis of this review. Most evidence indicates the presence of cognitive deficits in the first 2 weeks post-MTBI, and some evidence suggests that complete recovery may take 6 months or a year. A small number of studies indicate that MTBI increases the risk of psychiatric illnesses and suicide.
  
  
  CONCLUSIONS
  Early cognitive deficits are common, and complete recovery may be prolonged. Conclusions about mortality post-MTBI are limited. This review has implications for expected recovery after MTBI and MTBI-related health sequelae. Well-designed confirmatory studies are needed to understand the medium- to long-term consequences of MTBI and to further evaluate the effect of prior MTBI and injury severity on recovery.
authors.affiliation: School of Public Health and Alberta Centre for Injury Control and Research, University of Alberta, Edmonton, Canada. Electronic address: lcarroll@ualberta.ca.
authors.forename: Linda J
authors.initials: LJ
authors.lastname: Carroll
authors.affiliation: Division of Health Care and Outcomes Research, Toronto Western Research Institute, University Health Network, University of Toronto, Toronto, Ontario, Canada; Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada; Institute of Sports Science and Clinical Biomechanics, Faculty of Health, University of Southern Denmark, Odense, Denmark; Division of Epidemiology, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada.
authors.forename: J David
authors.initials: JD
authors.lastname: Cassidy
authors.affiliation: Division of Health Care and Outcomes Research, Toronto Western Research Institute, University Health Network, University of Toronto, Toronto, Ontario, Canada; Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Carol
authors.initials: C
authors.lastname: Cancelliere
authors.affiliation: Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada; Division of Epidemiology, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada; Faculty of Health Sciences, University of Ontario Institute of Technology-Canadian Memorial Chiropractic College Centre for the Study of Disability Prevention and Rehabilitation, Toronto, Ontario, Canada.
authors.forename: Pierre
authors.initials: P
authors.lastname: Côté
authors.affiliation: Division of Health Care and Outcomes Research, Toronto Western Research Institute, University Health Network, University of Toronto, Toronto, Ontario, Canada; Division of Epidemiology, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Cesar A
authors.initials: CA
authors.lastname: Hincapié
authors.affiliation: Division of Epidemiology, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada; Department of Health Sciences, Lakehead University, Thunder Bay, Ontario, Canada; Institute of Work and Health, Toronto, Ontario, Canada; Division of Human Sciences, Northern Ontario School of Medicine, Lakehead University, Thunder Bay, Ontario, Canada.
authors.forename: Vicki L
authors.initials: VL
authors.lastname: Kristman
authors.affiliation: Division of Epidemiology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Lena W
authors.initials: LW
authors.lastname: Holm
authors.affiliation: Department of Clinical Sciences, Rehabilitation Medicine, Karolinska Institutet, Danderyd University Hospital, Stockholm, Sweden.
authors.forename: Jörgen
authors.initials: J
authors.lastname: Borg
authors.affiliation: Department of Clinical Sciences, Rehabilitation Medicine, Karolinska Institutet, Danderyd University Hospital, Stockholm, Sweden.
authors.forename: Catharina
authors.initials: C
authors.lastname: Nygren-de Boussard
authors.affiliation: Institute of Sports Science and Clinical Biomechanics, Faculty of Health, University of Southern Denmark, Odense, Denmark; Nordic Institute of Chiropractic and Clinical Biomechanics, Odense, Denmark.
authors.forename: Jan
authors.initials: J
authors.lastname: Hartvigsen
mesh_terms: D001930:Brain Injuries / Q000175:diagnosis* / Q000401:mortality / Q000523:psychology*; D003072:Cognition Disorders / Q000209:etiology; D006801:Humans; D001523:Mental Disorders / Q000209:etiology*; D011379:Prognosis; D013405:Suicide / Q000706:statistics & numerical data; D013997:Time Factors; D015599:Trauma Severity Indices
keywords: Craniocerebral trauma; Mortality; Recovery of function; Rehabilitation