Strengthening the quality of longitudinal research into cognitive-communication recovery after traumatic brain injury: A systematic review

Abstract

Purpose: (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.

Method: Thirteen health literature databases were accessed up until July 2014.

Main measures: 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.

Result: 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.

Conclusion: 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.

Keywords:

• Cognitive-communication
• recovery
• prognosis
• systematic review
• traumatic brain injury

Acknowledgements

The authors thank Rachael Rietdijk for reliability; and Amatullah Kadous, Laura Lincoln and Stephanie Weir for research assistance.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this paper. Elise Elbourn is in receipt of a National Health & Medical Research Council (NHMRC) of Australia Scholarship (#GNT1056000). Leanne Togher is in receipt of a NHMRC Grant (#632681) and is the recipient of a NHMRC Senior Research Fellowship.