title: Methodological issues and research recommendations for prognosis after mild traumatic brain injury: results of the International Collaboration on Mild Traumatic Brain Injury Prognosis.
abstract: The International Collaboration on Mild Traumatic Brain Injury (MTBI) Prognosis performed a comprehensive search and critical review of the literature from 2001 to 2012 to update the 2002 best-evidence synthesis conducted by the World Health Organization Collaborating Centre for Neurotrauma, Prevention, Management and Rehabilitation Task Force on the prognosis of MTBI. Of 299 relevant studies, 101 were accepted as scientifically admissible. The methodological quality of the research literature on MTBI prognosis has not improved since the 2002 Task Force report. There are still many methodological concerns and knowledge gaps in the literature. Here we report and make recommendations on how to avoid methodological flaws found in prognostic studies of MTBI. Additionally, we discuss issues of MTBI definition and identify topic areas in need of further research to advance the understanding of prognosis after MTBI. Priority research areas include but are not limited to the use of confirmatory designs, studies of measurement validity, focus on the elderly, attention to litigation/compensation issues, the development of validated clinical prediction rules, the use of MTBI populations other than hospital admissions, continued research on the effects of repeated concussions, longer follow-up times with more measurement periods in longitudinal studies, an assessment of the differences between adults and children, and an account for reverse causality and differential recall bias. Well-conducted studies in these areas will aid our understanding of MTBI prognosis and assist clinicians in educating and treating their patients with MTBI.
authors.affiliation: Department of Health Sciences, Lakehead University, Thunder Bay, Ontario, Canada; Division of Human Sciences, Northern Ontario School of Medicine, Lakehead University, Thunder Bay, Ontario, Canada; Institute for Work and Health, Toronto, Ontario, Canada; Division of Epidemiology, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada. Electronic address: vkristman@lakeheadu.ca.
authors.forename: Vicki L
authors.initials: VL
authors.lastname: Kristman
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: Alison K
authors.initials: AK
authors.lastname: Godbolt
authors.affiliation: Univ. Bordeaux, ISPED, Centre INSERM U897-Epidemiologie-Biostatistique, F-33000 Bordeaux, France; INSERM, ISPED, Centre INSERM U897-Epidemiologie-Biostatistique, F-33000 Bordeaux, France; CHU de Bordeaux, Pole de sante publique, Service d'information medicale, F-33000 Bordeaux, France.
authors.forename: L Rachid
authors.initials: LR
authors.lastname: Salmi
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: School of Public Health and Alberta Centre for Injury Control and Research, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: Linda J
authors.initials: LJ
authors.lastname: Carroll
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: 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.
authors.forename: Jan
authors.initials: J
authors.lastname: Hartvigsen
authors.affiliation: Department of Health Sciences, Lakehead University, Thunder Bay, Ontario, Canada.
authors.forename: Uko
authors.initials: U
authors.lastname: Abara
authors.affiliation: Division of Health Care and Outcomes Research, Toronto Western Research Institute, University Health Network, University of Toronto, Toronto, Ontario, Canada.
authors.forename: James
authors.initials: J
authors.lastname: Donovan
authors.affiliation: Division of Epidemiology, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada; 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.
authors.forename: J David
authors.initials: JD
authors.lastname: Cassidy
mesh_terms: D015982:Bias; D035843:Biomedical Research / Q000379:methods* / Q000592:standards; D001924:Brain Concussion / Q000145:classification / Q000175:diagnosis; D001930:Brain Injuries / Q000145:classification* / Q000175:diagnosis*; D005500:Follow-Up Studies; D015600:Glasgow Coma Scale; D006801:Humans; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results; D015599:Trauma Severity Indices; D014944:World Health Organization
keywords: Brain concussion; Epidemiology; Injuries; Methods; Rehabilitation; Research