Strengthening the quality of longitudinal research into cognitive-communication recovery after traumatic brain injury: A systematic review.
(i) To systematically review longitudinal and prognostic studies relating to the trajectory of cognitive-communication recovery after TBI and (ii) to provide recommendations to strengthen future research.



Thirteen health literature databases were accessed up until July 2014.



Articles were screened systematically against pre-determined inclusion and exclusion criteria. Quality reviews were performed on the selected articles using a modified Downs & Black Rating Scale. Two independent reviewers performed the reviews.



Sixteen longitudinal and prognostic articles met the inclusion criteria. There was evidence of either maintenance or improvement of cognitive-communication skills during the first 3 years post-injury. However, the studies did not provide detailed recovery trajectories, by failing to evaluate numerous data points over time. No studies evaluated recovery beyond 3 years post-injury. Injury severity, lesion location, brain volume loss and conversation skills may predict specific cognitive-communication outcomes. There was high variability in study characteristics and measures.



There is currently scarce evidence regarding cognitive-communication recovery and prognosis. People with TBI may recover or maintain pre-morbid cognitive-communication skills during the early rehabilitation stage. Further research detailing the recovery trajectory with a view to evaluating predictive factors is strongly indicated. Guidelines for future research are provided.
a Faculty of Health Sciences; Disability and Communication Research Group Australia , The University of Sydney , Sydney , Australia ; and.|b National Health and Medical Research Council Centre of Research Excellence in Brain Recovery, The University of New South Wales , Sydney , Australia.
Elise
E
Elbourn
a Faculty of Health Sciences; Disability and Communication Research Group Australia , The University of Sydney , Sydney , Australia ; and.|b National Health and Medical Research Council Centre of Research Excellence in Brain Recovery, The University of New South Wales , Sydney , Australia.
Leanne
L
Togher
a Faculty of Health Sciences; Disability and Communication Research Group Australia , The University of Sydney , Sydney , Australia ; and.|b National Health and Medical Research Council Centre of Research Excellence in Brain Recovery, The University of New South Wales , Sydney , Australia.
Belinda
B
Kenny
a Faculty of Health Sciences; Disability and Communication Research Group Australia , The University of Sydney , Sydney , Australia ; and.|b National Health and Medical Research Council Centre of Research Excellence in Brain Recovery, The University of New South Wales , Sydney , Australia.
Emma
E
Power
D000070642:Brain Injuries, Traumatic / Q000150:complications*; D003071:Cognition; D003072:Cognition Disorders / Q000209:etiology; D003142:Communication; D003147:Communication Disorders / Q000209:etiology; D006801:Humans; D008137:Longitudinal Studies; D011379:Prognosis; D020127:Recovery of Function
Cognitive-communication; prognosis; recovery; systematic review; traumatic brain injury