Methodological Issues and Research Recommendations for Prognosis After Mild Traumatic Brain Injury: Results of the International Collaboration on Mild Traumatic Brain Injury Prognosis  Vicki L. Kristman, PhD, Jörgen Borg, MD, PhD, Alison K. Godbolt, MBChB, MD, L. Rachid Salmi, MD, PhD, Carol Cancelliere, DC, MPH, Linda J. Carroll, PhD, Lena W. Holm, DrMedSc, Catharina Nygren-de Boussard, MD, PhD, Jan Hartvigsen, PhD, Uko Abara, BHSc, James Donovan, DC, J. David Cassidy, PhD, DrMedSc  Archives of Physical Medicine and Rehabilitation  Volume 95, Issue 3, Pages S265-S277 (March 2014) DOI: 10.1016/j.apmr.2013.04.026 Copyright © 2014 American Congress of Rehabilitation Medicine Terms and Conditions

Fig 1 Example of confounding in MTBI research. This diagram shows that if cases of MTBI are more likely than a comparison group of musculoskeletal (MSK) injuries to be depressed, and those with depression are more likely to report poor recovery 5 days postinjury, then the MTBI may erroneously be considered the cause of poor recovery. This illustrates a confounding effect due to depression. Archives of Physical Medicine and Rehabilitation 2014 95, S265-S277DOI: (10.1016/j.apmr.2013.04.026) Copyright © 2014 American Congress of Rehabilitation Medicine Terms and Conditions