Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-18T00:38:08.847Z Has data issue: false hasContentIssue false

Diagnostic efficiency of demographically corrected Wechsler Adult Intelligence Scale-III and Wechsler Memory Scale-III indices in moderate to severe traumatic brain injury and lower education levels

Published online by Cambridge University Press:  01 November 2009

ALEXANDRA J. WALKER*
Affiliation:
Department of Psychology, Macquarie University, Sydney, Australia Brain Injury Rehabilitation Service, Westmead Hospital, Sydney, Australia
JENNIFER BATCHELOR
Affiliation:
Department of Psychology, Macquarie University, Sydney, Australia
E. ARTHUR SHORES
Affiliation:
Department of Psychology, Macquarie University, Sydney, Australia
MIKE JONES
Affiliation:
Department of Psychology, Macquarie University, Sydney, Australia
*
*Correspondence and reprint requests to: Alexandra J. Walker, Brain Injury Rehabilitation Service, Westmead Hospital, PO Box 533, Wentworthville NSW, 2145, Australia. E-mail: [email protected]

Abstract

Despite the sensitivity of neuropsychological tests to educational level, improved diagnostic accuracy for demographically corrected scores has yet to be established. Diagnostic efficiency statistics of Wechsler Adult Intelligence Scale-III (WAIS-III) and Wechsler Memory Scale-III (WMS-III) indices that were corrected for education, sex, and age (demographically corrected) were compared with age corrected indices in individuals aged 16 to 75 years with moderate to severe traumatic brain injury (TBI) and 12 years or less education. TBI participants (n = 100) were consecutive referrals to an outpatient rehabilitation service and met careful selection criteria. Controls (n = 100) were obtained from the WAIS-III/WMS-III standardization sample. Demographically corrected indices did not provide higher diagnostic efficiency than age corrected indices and this result was supported by reanalysis of the TBI group against a larger and unmatched control group. Processing Speed Index provided comparable diagnostic accuracy to that of combined indices. Demographically corrected indices were associated with higher cut-scores to maximize overall classification, reflecting the upward adjustment of those scores in a lower education sample. This suggests that, in clinical practice, the test results of individuals with limited education may be more accurately interpreted with the application of demographic corrections. Diagnostic efficiency statistics are presented, and future research directions are discussed. (JINS, 2009, 15, 938–950.)

Type
Research Articles
Copyright
Copyright © The International Neuropsychological Society 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Babor, T.F., Higgins-Biddle, J.C., Saunders, J.B., & Monteira, M.G. (2001). AUDIT: The Alcohol Use Disorders Identification Test: Guidelines for use in Primary Health Care: Geneva: World Health Organization.Google Scholar
Babyak, M.A. (2004). What you see may not be what you get: A brief, nontechnical introduction to overfitting in regression-type models. Psychosomatic Medicine, 66, 411421.Google Scholar
Bennett, P.C., Ong, B., & Ponsford, J. (2005). Assessment of executive dysfunction following traumatic brain injury: Comparison of the BADS with other clinical neuropsychological measures. Journal of the International Neuropsychological Society, 11, 606613.CrossRefGoogle ScholarPubMed
Blake, T.M., Fichtenberg, N.T., & Abeare, C.A. (2009). Clinical utility of demographically corrected WAIS-III subtest scores after traumatic brain injury. The Clinical Neuropsychologist, 23, 373384.CrossRefGoogle ScholarPubMed
Busch, R.M., McBride, A., Curtiss, G., & Vanderploeg, R.D. (2005). The components of executive functioning in traumatic brain injury. Journal of Clinical and Experimental Neuropsychology, 27, 10221032.CrossRefGoogle ScholarPubMed
Carstairs, J.R., Myors, B., Shores, E.A., & Fogarty, G. (2006). Influence of language background on tests of cognitive abilities: Australian data. Australian Psychologist, 41, 4854.CrossRefGoogle Scholar
Cohen, J. (1988). Statistical Power Analysis for the Behavioral Sciences (2nd ed.). New York: Academic Press.Google Scholar
Donders, J., Tulsky, D.S., & Zhu, J. (2001). Criterion validity of new WAIS-III subtest scores after traumatic brain injury. Journal of the International Neuropsychological Society, 7, 892898.CrossRefGoogle ScholarPubMed
Dori, G.A., & Chelune, G.J. (2004). Education-stratified base-rate information on discrepancy scores within and between the Wechsler Adult Intelligence Scale-Third Edition and the Wechsler Memory Scale-Third Edition. Psychological Assessment, 16, 146154.CrossRefGoogle ScholarPubMed
Finlayson, M., Johnson, K., & Reitan, R. (1977). Relationship of level of education to neuropsychological measures in brain-damaged and non-brain-damaged adults. Journal of Consulting and Clinical Psychology, 45, 536542.CrossRefGoogle ScholarPubMed
Fisher, D.C., Ledbetter, M.F., Cohen, N.J., Marmor, D., & Tulsky, D.S. (2000). WAIS-III and WMS-III profiles of mildly to severely brain-injured patients. Applied Neuropsychology, 7, 126132.CrossRefGoogle ScholarPubMed
Fork, M., Bartels, C., Ebert, A.D., Grubich, C., Synowitz, H., & Wallesch, C.W. (2005). Neuropsychological sequelae of diffuse traumatic brain injury. Brain Injury, 19, 101108.CrossRefGoogle ScholarPubMed
Griffin, S.L. (2002). Ecological validity of neuropsychological assessment in severe traumatic brain injury. Dissertation Abstracts International: Section B: The Sciences and Engineering, 62.Google Scholar
Grimes, D.A., & Schulz, K.F. (2005). Refining clinical diagnosis with likelihood ratios. Lancet, 365, 15001505.CrossRefGoogle ScholarPubMed
Heaton, R.K., Taylor, M.J., & Manly, J. (2003). Demographic effects and use of demographically corrected norms with the WAIS-III and WMS-III. In Tulsky, D.S., Saklofske, D.H., Chelune, G.J., Heaton, R.K., Ivnik, R.J., Bornstein, R., Prifitera, A. & Ledbetter, M.F. (Eds.), Clinical interpretation of the WAIS-III and WMS-III (pp. 183219). San Diego, CA: Academic Press.Google Scholar
Iverson, G.L., & Tulsky, D.S. (2003). Detecting malingering on the WAIS-III: Unusual Digit Span performance patterns in the normal population and in clinical groups. Archives of Clinical Neuropsychology, 18, 19.CrossRefGoogle ScholarPubMed
Ivnik, R.J., Smith, G.E., Verhan, J.H., Boeve, B.F., Tangalos, E.G., & Petersen, R.P. (2001). Understanding the diagnostic capabilities of cognitive tests. The Clinical Neuropsychologist, 15, 114124.CrossRefGoogle ScholarPubMed
Langeluddecke, P.M., & Lucas, S.K. (2003). Wechsler Adult Intelligence Scale-Third Edition findings in relation to severity of brain injury in litigants. Clinical Neuropsychologist, 17, 273284.CrossRefGoogle ScholarPubMed
Langeluddecke, P.M., & Lucas, S.K. (2005). WMS-III Findings in litigants following moderate to extremely severe brain trauma. Journal of Clinical and Experimental Neuropsychology, 27, 576590.CrossRefGoogle ScholarPubMed
Malec, J.F., Brown, A.W., Leibson, C.L., Flaada, J.T., Mandrekar, J.N., Diehl, N.N., et al. (2007). The Mayo classification system for traumatic brain injury severity. Journal of Neurotrauma, 24, 14171424.CrossRefGoogle ScholarPubMed
Martin, T.A., Donders, J., & Thompson, E. (2000). Potential of and problems with new measures of psychometric intelligence after traumatic brain injury. Rehabilitation Psychology, 45, 402408.CrossRefGoogle Scholar
Matarazzo, J.D. (1972). Wechsler’s Measurement and Appraisal of Adult Intelligence: Fifth and enlarged edition. New York: Oxford University Press.Google Scholar
Matarazzo, J.D., & Herman, D.O. (1984). Relationship of education and IQ in the WAIS–R standardization sample. Journal of Consulting and Clinical Psychology, 52, 631634.CrossRefGoogle Scholar
Miller, L.J., Ryan, J.J., Carruthers, C.A., & Cluff, R.B. (2004). Brief screening indexes for malingering: A confirmation of vocabulary minus digit span from the WAIS-III and the rarely missed index from the WMS-III. Clinical Neuropsychologist, 18, 327333.CrossRefGoogle ScholarPubMed
Mittenberg, W., Theroux, S., Aguila-Puentes, G., Bianchini, K., Greve, K., & Rayls, K. (2001). Identification of malingered head injury on the Wechsler Adult Intelligence Scale- 3rd Edition. The Clinical Neuropsychologist, 15, 440445.Google ScholarPubMed
Peat, J., & Barton, B. (2005). Medical Statistics: A Guide to Data Analysis and Critical Appraisal. New Delhi: Blackwell Publishing.CrossRefGoogle Scholar
Sherrill-Pattison, S., Donders, J., & Thompson, E. (2000). Influence of demographic variables on neuropsychological test performance after traumatic brain injury. The Clinical Neuropsychologist, 14, 496503.CrossRefGoogle ScholarPubMed
Shores, E.A., & Carstairs, J.R. (2000). The Macquarie University Neuropsychological Normative Study (MUNNS): Australian norms for the WAIS-R and WMS-R. Australian Psychologist, 35, 4159.CrossRefGoogle Scholar
Shores, E.A., Marosszeky, J.E., Sandanam, J., & Batchelor, J. (1986). Preliminary validation of a clinical scale for measuring the duration of post-traumatic amnesia. Medical Journal of Australia, 144, 569572.CrossRefGoogle ScholarPubMed
Steyerberg, E.W., Eijkemans, M.J., Harrell, F.E. Jr, & Habbema, J.D,. (2001). Prognostic modeling with logistic regression analysis: In search of a sensible strategy in small data sets. Medical Decision Making, 21, 4556.CrossRefGoogle ScholarPubMed
Strauss, S.E., Richardson, W.S., Glasziou, P., & Haynes, R.B. (2005). Evidence-Based Medicine: How to Practice and Teach EBM (3rd ed.). Edinburgh: Elsevier Churchill Livingstone.Google Scholar
Strong, C.A., Donders, J., & Van Dyke, S. (2005). Validity of demographically corrected norms for the WAIS-III. Journal of Clinical and Experimental Neuropsychology, 27, 746758.CrossRefGoogle ScholarPubMed
Taylor, M.J., & Heaton, R.K. (2001). Sensitivity and specificity of WAIS-III/WMS-III demographically corrected factor scores in neuropsychological assessment. Journal of the International Neuropsychological Society, 7, 867874.CrossRefGoogle ScholarPubMed
Teasdale, G.M., & Jennett, B. (1974). Assessment of coma and impaired consciousness. A practical scale. Lancet, 2, 8184.CrossRefGoogle ScholarPubMed
The Psychological Corporation. (1997). WAIS-III WMS-III Technical Manual. San Antonio, TX: The Psychological Corporation.Google Scholar
The Psychological Corporation. (2001a). WAIS-III/WMS-III/WIAT-II Scoring Assistant. San Antonio, TX: The Psychological Corporation.Google Scholar
The Psychological Corporation. (2001b). Wechsler Test of Adult Reading: Manual. San Antonio, TX: The Psychological Corporation.Google Scholar
Tombaugh, T.N. (1996). Test of Memory Malingering TOMM. New York: Multi-Health Systems.Google Scholar
Vanderploeg, R.D., Axelrod, B.N., Sherer, M., Scott, J., & Adams, R.L. (1997). Importance of demographic adjustments on neuropsychological test performance: A response to Reitan and Wolfson (1995). Clinical Neuropsychologist, 11, 210217.CrossRefGoogle Scholar
Wechsler, D. (1997a). Wechsler Adult Intelligence Scale-Third Edition. San Antonio, TX: The Psychological Corporation.Google Scholar
Wechsler, D. (1997b). Wechsler Memory Scale-Third Edition. San Antonio, TX: The Psychological Corporation.Google Scholar