Subtypes of Emotional and Behavioural Sequelae in Patients With Traumatic Brain Injury

This study examined patterns of emotional and behavioural sequelae in 300 individuals who sustained a traumatic brain injury (TBI). Participants were obtained through the Adult Acquired Brain Injury Program at Chedoke Hospital in Hamilton, Ontario, based on the following inclusionary criteria: (1) single incident of TBI; (2) no history of additional neurological diseases; (3) time postinjury < or =8.5 years; (4) WAIS-R FSIQ >85 and/or estimated reading skills above grade 5 level; and (5) valid Minnesota Multiphasic Personality Inventory (MMPI) profiles (i.e., F<90, L<66, and K<66). MMPI profiles of these individuals, in randomly split samples of 150 per group, were subjected to a three-step cluster analytic approach. A six-cluster solution was adequately replicated across samples and across clustering techniques. The identified subtypes included profiles indicative of: (1) no concerns or normal functioning; (2) mild somatic and pain concerns; (3) mild internalizing difficulties; (4) marked disinhibition and externalizing behavioural difficulties; (5) marked internalizing difficulties; and (6) marked somatic, internalizing, and externalizing behavioural disturbances. Members of the Externalized subtype were significantly younger in age than those in the other five subtypes, and more likely to be single than those in the Internalized subtype. Individuals in the Internalized subtype tended to be married, have longer times postaccident, and lower WAIS-R Verbal Intelligence Quotients than those comprising the Normal subtype.