Efficacy of Neuropsychological Evaluations in Long Term Rehabilitation

Philip Schatz, Ph.D., Saint Joseph's University
Douglas L. Chute, Ph.D., Drexel University

Abstract

Acute care, rehabilitation hospital, and post-acute rehabilitation records were analyzed for 300 moderate and severe TBI patients enrolled in the Pennsylvania Head Injury Program. Only 35% (N=106) subjects received Neuro-psychological evaluations at some point in their rehabilitation.

Subjects were divided into independent groups on the basis of whether or not they received neuropsychological evaluations; groups were matched for severity of coma, length of loss of consciousness, acute care length of stay, and functional ability at discharge from primary rehabilitation. Analysis of variance revealed no significant difference between groups on a measure of functional independence up to 7 years post trauma.

Subjects attending multiple rehabilitation facilities were significantly more likely to receive neuropsychological evaluations (p<.0001), and subjects receiving neuro-psychological evaluations who attended more than one rehabilitation hospital had significantly higher ratings of functional ability at discharge from primary rehabilitation (p<.01) and ultimately achieved a higher level of independence (p<.05).

Results suggest that following moderate-to-severe traumatic brain injury, only a discrete sample of subjects receive and benefit from neuropsychological evaluations. Results further suggest that a majority of these evaluations are likely to guide rehabilitation planning for subjects more likely to remain "in the system".


Introduction

In this study, we examine the relationship between severity of injury, utility of neuropsychological evaluations and length of rehabilitation, and their ultimate effect on functional level of independence.

Neuropsychological evaluations are frequently used in rehabilitation following traumatic brain injury for the purposes of determining the nature and extent of neurological damage, documenting functional strengths and weaknesses, and for guiding treatment planning. Inpatient and outpatient rehabilitation programs are also considered a valuable part of ongoing treatment for traumatic brain injuries.

In a large comprehensive state-wide sample of moderate-to-severe TBI survivors, neuropsychological evaluations were present in the medical and rehabilitation charts of only 106 of a group of 300 patients followed over a 6-year period (Horowitz, Schatz, & Chute, 1996). A 35% rate of formal neuropsychological evaluation was much lower than might normally be expected. Equally surprising, significantly longer rehabilitation stays were found to produce no significant improvement on functional outcomes for patients matched for severity of injury (Schatz & Chute, 1995).


Methods

Subjects:
Subjects were 300 individuals considered to be domiciled in the state of Pennsylvania at the time of their head injury who enrolled in the Pennsylvania Head Injury Program. Inclusion in the study was contingent upon:
  • documented evidence of a traumatic brain injury
  • measureable outcome rating at two+ years post-injury

Procedures:

Retrospective inspection of Pennsylvania Head Injury Program files was performed, coding Glasgow Coma Scale scores, length of loss of consciousness, length of acute and rehabilitation hospitalization, number of rehabilitation hospitalizations, presence of neuropsychological evaluations. Disability Rating Scale (DRS) scores and Functional Independence Level (Schatz & Chute, 1995) scores were coded from rehabilitation and post-acute rehabilitation hospital discharge summaries and/or Pennsylvania Head Injury Program case management reports. Where specific scores were not recorded, patient information within these documents was used to extrapolate DRS and FIL scores. Alternate raters were used to evaluate these ratings, and inter-rater reliability was calculated at .80 for FIL scores and .90 for DRS scores.

Results

Subjects were divided into independent groups on the basis of whether or not they received neuropsychological evaluations. Subjects with neuropsychological testing vs. no neuro-psychological testing were matched for Glascow Coma Scale scores, length of loss of consciousness, acute care length of stay, and Disability Rating Scale score at discharge from primary rehabilitation. Results showed no significant effects of neuropsychological testing on measures of functional outcome.

Subjects were then divided into independent groups on the basis of the number of rehabilitation hospitals attended. Subjects attending multiple rehabilitation facilities were significantly more likely to receive neuropsychological evaluations [X2(1)=19.29, p<.0001]. Analysis of variance revealed that subjects receiving neuropsychological evaluations who attended more than one rehabilitation hospital had significantly higher ratings of functional ability at discharge from primary rehabilitation rehabilitation [F(1,104)=6.48, p<.01] and ultimately achieved a higher level of independence [F(1,124)=4.65 p<.05].


Implications

Following moderate-to-severe traumatic brain injury, neuropsychological evaluations are rendered later in rehabilitation.

We speculate that many traumatic brain injury survivors incur severe impairments which initially prevent participation in formal neuropsychological evaluations.

Neuropsychological evaluations appear to be under-utilized in rehabilitation, as indicated by our 35% administration rate in the Commonwealth of Pennsylvania.

Patients who ultimately receive neuropsychological evaluations have better outcomes.


Table 1. Neuropsychological evaluations by number of rehabilitation hospital attended.
Neuropsychological
Evaluation?
Number of Rehab. Hospitals Attended
 OneMultiple
Yes1458
No7068
X2(1)=19.29, p<.0001


Table 2. Effects of neuropsychological evaluations and number of rehabilitation hospital attended on functional outcome variables.

Rating of Functional Ability

Number of Rehabilitation Hospitals Attended
One
Multiple
Neuropsych Evaluation?
Neuropsych Evaluation?

Yes
No
Yes
No

DRS at discharge from Primary Rehab

9.8
8.7
8.4
10.6**

Functional Independence Level

6.3
7.0
7.0
6.3*

**[F(1,104)=6.48, p&lt;.01]
*[F(1,124)=4.65 p&lt;.05]