Traumatic brain injury (TBI) is not a singular impairment. It originates from many different sources and represents diverse impairments that can dynamically affect almost any aspect of daily life. Hence, comprehensive, contextual and holistic perspectives are required to develop life care plans. As aptly noted 80 years ago, “it is not only the kind of injury that matters, but the kind of head” (Symonds, 1937). Multiple factors create the unique multivariate signature of each TBI. This includes the nature of injury onset; the intensity, inflection, nature, and foci of cerebral insult(s); comorbid injuries; the focus, time and quality of initial care; appropriateness of subsequent treatment; premorbid status; age at onset; history of neurological insult; and other issues. Attempting to ascribe TBI outcome to any singular factor is likely to be erroneous. For example, the Glasgow Coma Scale is often used to estimate initial injury severity, but singularly has limited prognostic value.
Howard T. Katz (2025) studied this question.