Characteristics of impaired awareness after traumatic brain injury MARK SHERER, 1,2 CORWIN BOAKE, 3,1 ELLEN LEVIN, 1,2 BERNARD V. SILVER, 1,2 GEORGE RINGHOLZ, 2 and WALTER M. HIGH, Jr. 2,1 1 The Institute for Rehabilitation and Research 2 Baylor College of Medicine, Houston, TX 3 University of Texas Health Science Center at Houston, Houston, TX (Received May 13, 1997; Revised September 19, 1997; Accepted November 17, 1997) Abstract Impaired awareness of the effects of brain injury is a commonly observed and poorly understood finding in traumatic brain injury survivors. Nonetheless, impaired awareness has been identified as a major factor in determining outcome for traumatic brain injury survivors. Review of previous studies of impaired awareness in this patient population revealed a number of preliminary findings regarding the nature of this phenomenon. The present paper presents the results of 2 new studies with a total of 111 traumatic brain injury patients conducted to bring further clarity to this area. Findings confirmed and extended many results of previous investigations. Specific findings included patient overestimation of functioning as compared to family member ratings, patient report of greater physical than nonphysical impairment, greater patient–family agreement on specific ratings of patient functioning than on general ratings, greater agreement of family and clinician ratings of patient functioning with each other than with patient self-ratings, and partial disagreement of different methods of measuring impaired awareness. (JINS, 1998, 4, 380–387.) Keywords: Impaired awareness, Traumatic brain injury, Characteristics, Measurement, Awareness Questionnaire INTRODUCTION Impaired awareness of deficits is a frequent finding after acquired brain injury (Goldstein, 1939; Weinstein & Kahn, 1955). Such impaired awareness has been described in patients with brain injury due to stroke, dementia, and trau- matic brain injury (McGlynn & Schacter, 1989). Clinicians working to rehabilitate patients who have suffered trau- matic brain injury generally agree that impaired self- awareness significantly complicates the rehabilitation process (Ben-Yishay et al., 1985; Prigatano & Fordyce, 1986). Con- sequently, there has been interest in developing methods of assessing unawareness so that its effect on rehabilitation out- come can be studied and the efficacy of treatment methods aimed at improving awareness can be assessed. Previous studies of impaired awareness in patients with traumatic brain injury have measured awareness in a number of ways using several different questionnaires and rating scales. These studies have produced a variety of prelimi- nary findings regarding the nature of impaired awareness. Some of these findings are inconsistent across studies or have not yet been replicated. The apparent inconsistency of some of these findings may be the result of the different ways that awareness has been measured in the various stud- ies. There has been only very limited investigation of the comparability of different methods of measuring aware- ness. The present paper presents a comprehensive review of previous findings regarding the nature of impaired aware- ness after traumatic brain injury. Methodologies used to mea- sure impaired awareness are also reviewed. Finally, the results of two new investigations of the characteristics of impaired awareness after traumatic brain injury are presented. Characteristics of Impaired Awareness Clinical observation suggests that impaired awareness after traumatic brain injury is a complicated phenomenon. Some patients, particularly in the acute period, may be unaware that they have suffered any injury at all. Other patients ad- Reprint requests to: Mark Sherer, Mississippi Methodist Rehabilita- tion Center, 1350 East Woodrow Wilson, Jackson, MS 39216. USA. E-mail: marks@mmrcrehab.org Journal of the International Neuropsychological Society (1998), 4, 380–387. Copyright © 1998 INS. Published by Cambridge University Press. Printed in the USA. 380