Brain Injury Model Systems National Research Articles

Risk Factors for Institutionalization After Traumatic Brain Injury Inpatient Rehabilitation.

To create a profile of individuals with traumatic brain injury (TBI) who received inpatient rehabilitation and were discharged to an institutional setting using characteristics measured at rehabilitation discharge. The Traumatic Brain Injury Model Systems National Database is a prospective, multicenter, longitudinal database for people with moderate to severe TBI. We analyzed data for participants enrolled from January 2002 to June 2012 who had lived in a private residence before TBI. This cross-sectional study used logistic regression analyses to identify sociodemographic factors, lengths of stay, and cognitive and physical functioning levels that differentiated patients discharged to institutional versus private settings. Older age, living alone before TBI, and lower levels of function at rehabilitation discharge (independence in locomotion, bladder management, comprehension, and social interaction) were significantly associated with higher institutionalization rates and provided the best models identifying factors associated with institutionalization. Institutionalization was also associated with decreased independence in bed-chair-wheelchair transfers and increased duration of posttraumatic amnesia. Individuals institutionalized after inpatient rehabilitation for TBI were older, lived alone before injury, had longer posttraumatic amnesia durations, and were less independent in specific functional characteristics. Research evaluating the effect of increasing postdischarge support and improving treatment effectiveness in these functional areas is recommended.

Prevalence of suicidal behaviour following traumatic brain injury: Longitudinal follow-up data from the NIDRR Traumatic Brain Injury Model Systems

Objective: This study utilized the Traumatic Brain Injury Model Systems (TBIMS) National Database to examine the prevalence of depression and suicidal behaviour in a large cohort of patients who sustained moderate-to-severe TBI.Method: Participants presented to a TBIMS acute care hospital within 72 hours of injury and received acute care and comprehensive rehabilitation in a TBIMS designated brain injury inpatient rehabilitation programme. Depression and suicidal ideation were measured with the Patient Health Questionnaire (PHQ-9). Self-reported suicide attempts during the past year were recorded at each follow-up examination, at 1, 2, 3, 10, 15 and 20 years post-injury.Results: Throughout the 20 years of follow-up, rates of depression ranged from 24.8–28.1%, suicidal ideation ranged from 7.0–10.1% and suicide attempts (past year) ranged from 0.8–1.7%. Participants who endorsed depression and/or suicidal behaviour at year 1 demonstrated consistently elevated rates of depression and suicidal behaviour 5 years after TBI.Conclusion: Compared to the general population, individuals with TBI are at greater risk for depression and suicidal behaviour many years after TBI. The significant psychiatric symptoms evidenced by individuals with TBI highlight the need for routine screening and mental health treatment in this population.

A Multidimensional Rasch Analysis of the Functional Independence Measure Based on the National Institute on Disability, Independent Living, and Rehabilitation Research Traumatic Brain Injury Model Systems National Database.

A number of studies have evaluated the psychometric properties of the Functional Independence Measure (FIM™) using Rasch analysis, although none has done so using the National Institute on Disability, Independent Living, and Rehabilitation Research Traumatic Brain Injury Model Systems National Database, a longitudinal database that captures demographic and outcome information on persons with moderate to severe traumatic brain injury across the United States. In the current study, we examine the psychometric properties of the FIM as represented by persons within this database and demonstrate that the FIM comprises three subscales representing cognitive, self-care, and mobility domains. These subscales were analyzed simultaneously using a multivariate Rasch model in combination with a time dependent concurrent calibration scheme with the goal of creating a raw score-to-logit transformation that can be used to improve the accuracy of parametric statistical analyses. The bowel and bladder function items were removed because of misfit with the motor and cognitive items. Some motor items exhibited step disorder, which was addressed by collapsing Categories 1-3 for Toileting, Stairs, Locomotion, Tub/Shower Transfers; Categories 1 and 2 for Toilet and Bed Transfers; and Categories 2 and 3 for Grooming. The strong correlations (r = 0.82-0.96) among the three subscales suggest they should be modeled together. Coefficient alpha of 0.98 indicates high internal consistency. Keyform maps are provided to enhance clinical interpretation and application of study results.

Another Look at the PART-O Using the Traumatic Brain Injury Model Systems National Database: Scoring to Optimize Psychometrics

ObjectiveTo integrate previous approaches to scoring the Participation Assessment with Recombined Tools-Objective (PART-O) in a unidimensional scale. DesignRetrospective analysis of PART-O data from the Traumatic Brain Injury Model Systems. SettingCommunity. ParticipantsData from individuals (N=469) selected randomly from participants who completed 1-year follow-up in the Traumatic Brain Injury Model Systems were used in Rasch model development. The model was subsequently tested on data from additional random samples of similar size at 1-, 2-, 5-, 10-, and >15-year follow-ups. InterventionsNot applicable. Main Outcome MeasurePART-O. ResultsAfter combining items for productivity and social interaction, the initial analysis at 1-year follow-up indicated relatively good fit to the Rasch model (person reliability=.80) but also suggested item misfit and that the 0-to-5 scale used for most items did not consistently show clear separation between rating levels. Reducing item rating scales to 3 levels (except combined and dichotomous items) resolved these issues and demonstrated good item level discrimination, fit, and person reliability (.81), with no evidence of multidimensionality. These results replicated in analyses at each additional follow-up period. ConclusionsModifications to item scoring for the PART-O resulted in a unidimensional parametric equivalent measure that addresses previous concerns about competing item relations, and it fit the Rasch model consistently across follow-up periods. The person-item map shows a progression toward greater community participation from solitary and dyadic activities, such as leaving the house and having a friend through social and productivity activities, to group activities with others who share interests or beliefs.

Predicting institutionalization after traumatic brain injury inpatient rehabilitation.

Risk factors contributing to institutionalization after inpatient rehabilitation for people with traumatic brain injury (TBI) have not been well studied and need to be better understood to guide clinicians during rehabilitation. We aimed to develop a prognostic model that could be used at admission to inpatient rehabilitation facilities to predict discharge disposition. The model could be used to provide the interdisciplinary team with information regarding aspects of patients' functioning and/or their living situation that need particular attention during inpatient rehabilitation if institutionalization is to be avoided. The study population included 7219 patients with moderate-severe TBI in the Traumatic Brain Injury Model Systems (TBIMS) National Database enrolled from 2002-2012 who had not been institutionalized prior to injury. Based on institutionalization predictors in other populations, we hypothesized that among people who had lived at a private residence prior to injury, greater dependence in locomotion, bed-chair-wheelchair transfers, bladder and bowel continence, feeding, and comprehension at admission to inpatient rehabilitation programs would predict institutionalization at discharge. Logistic regression was used, with adjustment for demographic factors, proxy measures for TBI severity, and acute-care length-of-stay. C-statistic and predictiveness curves validated a five-variable model. Higher levels of independence in bladder management (adjusted odds ratio [OR], 0.88; 95% CI 0.83, 0.93), bed-chair-wheelchair transfers (OR, 0.81 [95% CI, 0.83-0.93]), and comprehension (OR, 0.78 [95% CI, 0.68, 0.89]) at admission were associated with lower risks of institutionalization on discharge. For every 10-year increment in age was associated with a 1.38 times higher risk for institutionalization (95% CI, 1.29, 1.48) and living alone was associated with a 2.34 times higher risk (95% CI, 1.86, 2.94). The c-statistic was 0.780. We conclude that this simple model can predict risk of institutionalization after inpatient rehabilitation for patients with TBI.

An Introduction to Analyzing Dichotomous Outcomes in a Longitudinal Setting

An untapped wealth of temporal information is captured within the Traumatic Brain Injury Model Systems National Database. Utilization of appropriate longitudinal analyses can provide an avenue toward unlocking the value of this information. This article highlights 2 statistical methods used for assessing change over time when examination of noncontinuous outcomes is of interest where this article focuses on investigation of dichotomous responses. Specifically, the intent of this article is to familiarize the rehabilitation community with the application of generalized estimating equations and generalized linear mixed models as used in longitudinal studies. An introduction to each method is provided where similarities and differences between the 2 are discussed. In addition, to reinforce the ideas and concepts embodied in each approach, we highlight each method, using examples based on data from the Rocky Mountain Regional Brain Injury System.

Longitudinal Description of the Glasgow Outcome Scale-Extended for Individuals in the Traumatic Brain Injury Model Systems National Database: A National Institute on Disability and Rehabilitation Research Traumatic Brain Injury Model Systems Study

ObjectiveTo comprehensively describe the temporal patterns of global outcome after traumatic brain injury (TBI) in the Traumatic Brain Injury Model Systems National Database (TBIMS NDB). DesignLongitudinal prospective cohort study. SettingTBI Model Systems centers. ParticipantsPatients (N=3870) ≥16 years of age with moderate or severe TBI enrolled in the TBIMS NDB. InterventionsNone. Main Outcome MeasureGlasgow Outcome Scale-Extended (GOS-E). ResultsThe trajectory of the GOS-E scores is best described with a model of quadratic change, in which scores initially increase and peak approximately 10 years after the first GOS-E assessment, and then decrease. Change occurs most rapidly in the initial and final years of the timeline. There was significant variability in each growth parameter (P<.05). A reduced multilevel model was built, including all covariates (age at first GOS-E assessment, FIM, race, sex, rehabilitation length of stay) that related significantly to the growth parameters. An interactive tool was created to generate individual level trajectories based on various combinations of covariate values. Results provide an individual level account of the chronological progression of TBI outcomes, as measured by the GOS-E. ConclusionsIndividual growth curve analysis is a statistically rigorous approach to describe temporal change with respect to the GOS-E at the individual level for participants within the TBIMS NDB. Results indicated that, for individuals in the TBIMS NDB as a group, functional status as measured by the GOS-E initially improves, plateaus, and then begins to decline. Factors such as age at first GOS-E assessment, race, FIM score at rehabilitation admission, and rehabilitation length of stay were found to influence baseline GOS-E scores, as well as the rate and extent of both improvement and decline over time. Additional research may be required to determine the generalizability of these findings and the usefulness of this tool for clinical applications.

Longitudinal Description of the Disability Rating Scale for Individuals in the National Institute on Disability and Rehabilitation Research Traumatic Brain Injury Model Systems National Database

ObjectiveTo develop a detailed understanding of temporal change (ie, estimated trajectories) at the individual level as measured by the Disability Rating Scale (DRS). DesignIndividual growth curve (IGC) analysis of retrospective data obtained from the National Institute on Disability and Rehabilitation Research Traumatic Brain Injury (TBI) Model Systems National Database. SettingMulticenter longitudinal database study. ParticipantsIndividuals with TBI (N=8816) participating in the TBI Model Systems National Database project. InterventionsNot applicable. Main Outcome MeasureDRS. ResultsThe negative exponential consisting of 3 growth parameters (pseudointercept, asymptote, rate) was successfully used to predict trajectory of recovery on the DRS qualified by the following covariates: race, sex, level of education and age at admission, rehabilitation length of stay, and cognitive and motor FIM scores at rehabilitation admission. Based on these results, an interactive tool was developed to allow prediction of the trajectory of recovery for individuals and subgroups with specified characteristics on the selected covariates. ConclusionsWith the use of IGC analysis, the longitudinal trajectory of recovery on the DRS for individuals sharing common characteristics and traits can be described. This methodology allows researchers and clinicians to predict numerous individual-level trajectories through use of a web-based computer automated interactive tool.

Prior History of Traumatic Brain Injury Among Persons in the Traumatic Brain Injury Model Systems National Database

ObjectiveTo determine the association between demographic, psychosocial, and injury-related characteristics and traumatic brain injury (TBI) occurring prior to a moderate or severe TBI requiring rehabilitation. DesignSecondary data analysis. SettingTBI Model System inpatient rehabilitation facilities. ParticipantsPersons (N=4464) 1, 2, 5, 10, 15, or 20 years after TBI resulting in participation in the TBI Model System National Database. InterventionsNot applicable. Main Outcome MeasuresHistory of TBI prior to the TBI Model System Index injury, pre-Index injury demographic and behavioral characteristics, Index injury characteristics, post-Index injury behavioral health and global outcome. ResultsTwenty percent of the cohort experienced TBIs preceding the TBI Model System Index injury—80% of these were mild and 40% occurred before age 16. Pre- and post-Index injury behavioral issues, especially substance abuse, were highly associated with having had a prior TBI. Greater severity of the pre-Index injury as well as occurrence before age 6 often showed stronger associations. Unexpectedly, pre-Index TBI was associated with less severe Index injuries and better functioning on admission and discharge from rehabilitation. ConclusionsFindings suggest that earlier life TBI may have important implications for rehabilitation after subsequent TBI, especially for anticipating behavioral health issues in the chronic stage of recovery. Results provide additional evidence for the potential consequences of early life TBI, even if mild.

Extension of the Representativeness of the Traumatic Brain Injury Model Systems National Database

To extend the representativeness of the Traumatic Brain Injury Model Systems National Database (TBIMS-NDB) for individuals 16 years and older, admitted for acute, inpatient rehabilitation in the United States with a primary diagnosis of traumatic brain injury (TBI) analyses completed by Corrigan and colleagues by comparing this data set to national data for patients admitted to inpatient rehabilitation with identical inclusion criteria that included 3 additional years of data and 2 new demographic variables. Secondary analysis of existing data sets and extension of previously published analyses. Acute inpatient rehabilitation facilities. Patients 16 years and older with a primary rehabilitation diagnosis of TBI; the US TBI Rehabilitation population, n = 156 447; and the TBIMS-NDB population, n = 7373. None. Demographics, functional status, and length of stay in hospital. The TBIMS-NDB was largely representative of patients 16 years and older, admitted for rehabilitation in the United States with a primary diagnosis of TBI on or after October 1, 2001, and discharged as of December 31, 2010. The results of the extended analyses were similar to those reported by Corrigan and colleagues. Age accounted for the largest difference between the samples, with the TBIMS-NDB including a smaller proportion of patients 65 years and older than all those admitted for rehabilitation with a primary diagnosis of TBI in the United States. After partitioning each data set at age 65, most distributional differences found between samples were markedly reduced; however, differences in the preinjury vocational status of the employed and rehabilitation lengths of stay between 1 and 9 days remained robust. The subsamples of patients 64 years and younger were found to differ only slightly on all remaining variables, whereas those 65 years and older were found to have meaningful differences in insurance type and age distribution. These results reconfirm that the TBIMS-NDB is largely representative of patients with TBI receiving inpatient rehabilitation in the United States. Differences between the 2 data sets were found to be stable across the 3 additional years of data, and new differences were limited to those involving newly introduced variables. To use these data for population-based research, it is strongly recommended that statistical adjustment be conducted to account for the lower percentage of patients older than 65 years, inpatient rehabilitation stays less than 10 days, and preinjury vocational status in the TBIMS-NDB.

Representativeness of the Traumatic Brain Injury Model Systems National Database.

To determine whether the Traumatic Brain Injury Model Systems National Database (TBIMS-NDB) is representative of individuals aged 16 years and older admitted for acute, inpatient rehabilitation in the United States with a primary diagnosis of traumatic brain injury (TBI). Secondary analysis of existing data sets. Acute inpatient rehabilitation facilities. Patients aged 16 years and older with a primary rehabilitation diagnosis of TBI. Demographic characteristics, functional status, and hospital length of stay. Patients included in the TBIMS-NDB from October 2001 through December 2007 were largely representative of all individuals 16 years and older admitted for rehabilitation in the United States with a primary diagnosis of TBI. The major difference in distribution was age-the TBIMS-NDB cohort did not include as large a proportion of patients older than 65 years as were admitted for rehabilitation with a primary diagnosis of TBI in the United States. Distributional differences for age-related characteristics were observed; however, groups of patients partitioned at aged 65 years differed minimally, especially within the younger than 65 years subset. Regardless of age, the proportion of patients with a rehabilitation stay of 1 to 9 days was larger nationwide. Nationwide admissions showed an age distribution similar to patients discharged alive from acute care with moderate, severe or penetrating TBI. The proportion of patients aged 70 years and older admitted for TBI rehabilitation in the United States increased every year, a trend that was not evident in the general population, TBIMS-NDB or among TBI patients in acute care. These results provide substantial empirical evidence that the TBIMS-NDB is representative of patients receiving inpatient rehabilitation for TBI in the United States. Researchers utilizing the TBIMS-NDB may want to adjust statistically for the lower percentage of patients older than 65 years or those with stays less than 10 days.

An Introduction to Applying Individual Growth Curve Models to Evaluate Change in Rehabilitation: A National Institute on Disability and Rehabilitation Research Traumatic Brain Injury Model Systems Report

The abundance of time-dependent information contained in the Spinal Cord Injury and the Traumatic Brain Injury Model Systems National Databases, and the increased prevalence of repeated-measures designs in clinical trials highlight the need for more powerful longitudinal analytic methodologies in rehabilitation research. This article describes the particularly versatile analytic technique of individual growth curve (IGC) analysis. A defining characteristic of IGC analysis is that change in outcome such as functional recovery can be described at both the patient and group levels, such that it is possible to contrast 1 patient with other patients, subgroups of patients, or a group as a whole. Other appealing characteristics of IGC analysis include its flexibility in describing how outcomes progress over time (whether in linear, curvilinear, cyclical, or other fashion), its ability to accommodate covariates at multiple levels of analyses to better describe change, and its ability to accommodate cases with partially missing outcome data. These features make IGC analysis an ideal tool for investigating longitudinal outcome data and to better equip researchers and clinicians to explore a multitude of hypotheses. The goal of this special communication is to familiarize the rehabilitation community with IGC analysis and encourage the use of this sophisticated research tool to better understand temporal change in outcomes.

Descriptive Modeling of Longitudinal Outcome Measures in Traumatic Brain Injury: A National Institute on Disability and Rehabilitation Research Traumatic Brain Injury Model Systems Study

Establishing accurate mathematical models of outcome measures is essential in understanding change throughout the rehabilitation process. The goal of this study is to identify the best-fitting descriptive models for a set of commonly adopted outcome measures found within the Traumatic Brain Injury Model Systems National Database where the modeling is based on data submission through 2011 and the complete range of recorded time points since injury for each individual, where time points range from admission to rehabilitation to 20 years postinjury. The statistical methodology and the application of the methodology contained herein may be used to assist researchers and clinicians in (1) modeling the outcome measures considered, (2) modeling various portions of these outcomes by stratification and/or truncating time periods, (3) modeling longitudinal outcome measures not considered, and (4) establishing models as a necessary precursor in conducting individual growth curve analysis.

Poster 34: Racial and Sex Differences in Employment Outcomes After Traumatic Brain Injury

Objective: To examine racial and sex differences in employment outcome 1 year after a traumatic brain injury (TBI). Design: Retrospective study. Setting: Longitudinal dataset of the Traumatic Brain Injury Model Systems (TBIMS) National Database. Participants: People with moderate to severe TBI (4538 whites vs 2205 minorities) hospitalized between 1989 and 2006 in a TBIMS center. Interventions: Not applicable. Main Outcome Measures: Employment status (competitively employed vs unemployed) 1 year postinjury.

Comparison of the Traumatic Brain Injury (TBI) Model Systems National Dataset to a Population-Based Cohort of TBI Hospitalizations

Corrigan JD, Selassie AW, Lineberry LA, Millis SR, Wood KD, Pickelsimer EE, Rosenthal M. Comparison of the Traumatic Brain Injury (TBI) Model Systems national dataset to a population-based cohort of TBI hospitalizations. Objective To determine whether severity alone accounts for differences observed between a population-based cohort of acute care hospitalizations for traumatic brain injury (TBI) and the Traumatic Brain Injury Model Systems (TBIMS) national dataset. Design Prospective cohort. Setting Acute care hospitals in South Carolina and TBIMS rehabilitation centers. Participants Subjects enrolled in the TBIMS national dataset and the South Carolina TBI Follow-up Registry (SCTBIFR). Interventions Not applicable. Main Outcome Measures Comparable variables in the 2 datasets included demographic characteristics, etiology of injury, initial Glasgow Coma Scale score, Abbreviated Injury Scale score for the head region derived from International Classification of Diseases codes, presence of computed tomography (CT) abnormalities, acute hospital length of stay, and payer source. Results As hypothesized, TBIMS participants showed greater initial injury severity, frequency of abnormal CT scans, and longer lengths of acute care hospitalization, explaining over 75% of cohort membership. Counter to a priori hypotheses, when all other factors were held constant, there were also differences in racial and ethnic background and insurance payer source. Conclusions Differences between the TBIMS cohort and patients acutely hospitalized with TBI are primarily due to injury severity; however, an additional difference in payer source may need to be taken into account when generalizing findings. Results showed that TBIMS and SCTBIFR datasets are complementary, each having different strengths for understanding factors that impact long-term recovery after TBI. Recommendations are made for methodologic improvements in both data collection for the TBIMS and future outcome surveillance.

Poster 48: Functional Outcomes in Traumatic Brain Injury Survivors: How Do Hispanics Measure Up?

Objective: To examine the relationship between Hispanic ethnicity and functional outcome in traumatic brain injury (TBI) survivors. Design: Retrospective study. Setting: Longitudinal dataset of the Traumatic Brain Injury Model Systems National Database. Participants: 3114 individuals with moderate to severe TBI (2798 whites vs 316 Hispanics) hospitalized between 1989 and 2003. Interventions: Not applicable. Main Outcome Measures: Functional outcomes at 1-year follow-up (Disability Rating Scale [DRS], Glasgow Outcome Scale–Extended [GOS-E], FIM instrument, Community Integration Questionnaire [CIQ]). Results: At admission, Hispanics were less educated (P≤.001), earned less money (P≤.05), and were slightly younger (P≤.001) than whites. Hispanics were twice as likely to suffer a violence-related TBI. Hispanics had lower Glasgow Coma Scale scores (P≤.01) compared with whites but received similar minutes of rehabilitation therapies. Hispanics received significantly more minutes of psychotherapy (P≤.01) before discharge. Hispanic ethnicity was associated with poorer functional outcomes at 1 year postinjury (DRS, GOS-E, FIM, CIQ), after controlling for age, length of posttraumatic amnesia, injury severity, and preinjury educational level (P≤.05). Conclusions: Hispanics showed significantly reduced long-term functional outcome after rehabilitation relative to whites. Rehabilitation professionals must recognize the impact of individual differences and diverse sociodemographic, injury, and rehabilitation characteristics so that health disparities among TBI survivors can be reduced.

Descriptive Findings from the Traumatic Brain Injury Model Systems National Data Base

Objectives:To describe the current status of the Traumatic Brain Injury Model Systems (TBIMS) National Data Base and present major descriptive findings based on the original research and demonstration issues for which the database was developed, and to describe patient outcomes at discharge from inp