Personal Injury Law

Ruff Disputes Claim That Everyone Gets Better (Part 2)

By Bruce Stern

Dr. Ruff concluded his presentation by discussing the controversy over whether the residuals of mild TBI can be permanent. Quoting Tom Kay, Ph.D., Dr. Ruff said there were believers and non-believers. The non-believers do not believe that the effects can be permanent, relying on various meta-analysis papers and sport concussions studies.

Dr. Ruff discussed the limitations and problems with those who rely on meta- analysis studies. (See for instance Frenchman, K.A. et al. (2005). Neuropsychological studies of mild traumatic brain injury: a meta-analytic review of research since 1995. Journal of Clinical and Experimental Neuropsychology, 27, 334-51.

Belanger et al. (2005a). The neuropsychological impact of sports-related concussion: A meta-analysis. Journal of the International Neuropsychological Society, 11, 345–357.

Belanger et al. (2005b). Factors moderating neuropsychological outcomes following mild traumatic brain injury: a meta-analysis. Journal of the International Neuropsychological Society, 11, 215-27.

Binder, L.M. et al. (1997a). A review of mild head trauma. Part I: meta-analytic review of neuropsychological studies. Journal of Clinical and Experimental Neuropsychology, 19, 421–431.

Binder, L.M. et al. (1997b). A review of mild head trauma. Part II: clinical implications. Journal of Clinical and Experimental Neuropsychology, 19, 432–457.
Dr. Ruff explained that when performing a meta analysis, the studies used different diagnosis criteria, different time intervals between trauma and testing, failed to account for attrition rates, different test batteries that were used, poorly matched control groups and mixed clinical samples.

Dr. Ruff further explained that the sample size difficulties eliminated that subgroup that has persistent problems. Even the Frenchman paper acknowledged that a small subgroup did have persistent problems.

Turning to defense forensic neuropsychologist's reliance on sports concussion research, Dr. Ruff explained that that research while of very high quality used different diagnosis criteria than is used in clinical settings and employed different definitions.  The subjects studied in the sports concussion studies were younger and had less premorbid vulnerbilities. Also, many of the tests used were more of a screening test than a true battery. Finally many of those studied were wearing helmets at the time of injury. Anecdotally Dr. Ruff reported that some athletes acknowledged purposely doing poorly on pre testing so that in the event they were hurt that they would appear uninjured and thus able to return to play.

Dr. Ruff concluded by stating that there is a miserable minority that do not in fact fully recover from mild TBI.

Full post as published by Traumatic Brain Injury Law Blog on March 18, 2010 (boomark / email).