Letters to the Editor K. Asplund Department of Medicine University Hospital Umea, Sweden G. Boysen Department of Neurology Rigshospitalet Copenhagen, Denmark

References

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1. Van Gijn J: Measurement of outcome in stroke prevention trials. Cerebrovasc Dis 1992;2(suppl l):23-34 2. Asplund K: Clinimetrics in stroke research. Stroke 1988;18: 528-530 3. Orgogozo JM, Dartigues JF: Methodology of clinical trials in acute trials in acute cerebral ischemia: Survival, functional and neurological outcome measures. Cerebrovasc Dis 1991;l(suppl 1): 100-111 4. Orgogozo JM, Dartigues JF: Clinical trials in brain infarction: The question of assessment criteria, in Battistini N, Fiorani P, Courbier R, Plum F, Fieschi C (eds): Acute Brain Ischemia: Medical and Surgical Therapy. New York, Raven Press Publishers, 1986, pp 201-208 5. Scandinavian Stroke Study Group: Multicenter trial of hemodilution in ischemic stroke: Background and study protocol. Stroke 1985;16:885-890 6. Lindenstrom E, Boysen G, Christiansen LW, Hensen BR, Nielsen PW: Reliability of Scandinavian Neurological Stroke Scale. Cerebrovasc Dis 1991;l:103-107 7. Shinar D, Gross CR, Hier DB, Caplan LR, Price TR, Mohr JP, Wolf PA, Kase CS, Fishman IG, Wolf CL, Kunitz SC: Interobserver variability in the assessment of neurologic history and examination in the Stroke Data Bank. Arch Neurol 1985;42:557-565 8. Bebbington AC: Scaling indices of disablement. Br J Prev Soc Med 1977;31:122-126 9. Gelmers HJ, Gorter K, DeWeerdt CJ, Wiezer JHA: Assessment of interobserver variability in a Dutch multicenter study on acute ischemic stroke. Stroke 1988;19:709-711 10. Adams RJ, Meador KJ, Sethi KD, Grotta JC, Thomson DS: Graded neurologic scale for use in acute hemispheric stroke treatment protocols. Stroke 1987;18:665-669 11. Cot6 R, Battista RN, Wolfson C, Boucher J, Adams J, Hachinski V: The Canadian Neurological Scale: Validation and reliability assessment. Neurology 1989;39:638-643 12. Goldstein LB, Bertels C, Davis JN: Interrater reliability of the NIH stroke scale. Arch Neurol 1989;46:660-662 13. Candelise L: Stroke scores and scales. Cerebrovasc Dis 1992;2: 239-247

Response The unified stroke scale presented by Drs. Orgogozo, Asplund, and Boysen contains many elements that have been proven reliable between and within different observers. Yet the more essential issue of validity (does the scale truly measure what it sets out to measure?) is passed over with the assertion that the constituent scales are "reasonably valid." Although the stated purpose of "stroke scales" is to measure outcome, these scales are simply codifications of the neurological examination, developed for localizing lesions within the nervous system. Such a diagnostic instrument is essentially and irreparably unsuitable for measuring outcome. The irrelevance of stroke scales can be specified into at least four separate issues.1'2 The first problem is that outcome should be measured from the patient's perspective rather than the doctor's, at least in clinical trials that address medical practice. It is naive to assume that items such as eye movements, facial palsy, and muscle tone are adequate measures of how well a patient has recovered from his stroke. Some other scales even include reflexes! What really counts for patients is what they can do in life compared with what they want to do or were once able to do. A higher level of measurement is needed; that is, scales should measure function not at the level of the organ but at the level of the person (disability scales) or even at the level of social interaction (handicap scales).3 A widely used

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and reliable disability scale is the Barthel Index.4 True handicap scales have not yet been sufficiently developed, but reliable scales that contain some elements of social function are the Glasgow Outcome Scale 56 and the Rankin Scale. 78 Problem number two is that the traditional features of the neurological examination provide an astonishingly incomplete assessment of the human brain. The function of the brain as a whole cannot be reconstructed from such simple elements. Mood, initiative, and speed of thinking are some of the essential features of human life that can be severely affected by stroke but are sadly ignored in stroke scales. The answer is not to add yet more items but to choose a higher-level scale that takes account of all defects at the same time. The third problem with stroke scales is the weighting and adding up of separate items. Adding up arbitrary scores for disparate items such as orientation, limb strength, and language is as meaningless as adding up the value of blood urea, sodium, potassium, and glucose to make up an overall "metabolic score." And what can averaged values actually mean if a sum score of, say, 67 out of 100 fails to evoke a mental image even of a single individual? The fourth and last problem is that the quest for sensitivity (the ability of a scale to detect subtle differences) does not require the large number of categories proposed by stroke scales. In clinical trials, the "noise" caused by randomization of patients that differ greatly from each other far exceeds the inaccuracies of the method used to measure outcome.9 In addition, almost all the statistical information needed can be achieved by a small number of categories. To epitomize: A generally accepted measure for assessing the severity of stroke is badly needed, but in my view no neurological scoring system can fulfill this purpose. J. van Gyn, MD University Department of Neurology Utrecht, The Netherlands

References 1. Van Gijn J: Measurement of outcome in stroke prevention trials. Cerebrovasc Dis 1992;2(suppl l):23-34 2. Van Gijn J, Warlow CP: Down with stroke scales! Cerebrovasc Dis (in press) 3. International Classification of Impairments, Disabilities, and Handicaps. Geneva, World Health Organization, 1980 4. Wade DT, Langton HR: Functional abilities after stroke: Measurement, natural history and prognosis. J Neurol Neurosurg Psychiatry 1987;50:177-182 5. Jennett B, Bond M: Assessment of outcome after severe brain damage: A practical scale. Lancet 1975;l:480-484 6. Maas AJR, Braakman R, Schouten HJA, Minderhoud JM, van Zomeren AH: Agreement between physicians on assessment of outcome following severe head injury. / Neurosurg 1983;58:321-325 7. Van Swieten JC, Koudstaal PJ, Visser MC, Schouten HJA, van Gijn J: Interobserver agreement for the assessment of handicap in stroke patients. Stroke 1988;19:604-607 8. Bamford JL, Sandercook PAG, Warlow CP, Slattery J: Interobserver agreement for the assessment of handicap in stroke patients. Stroke 1989;20:828 9. Peto R: Monitoring cancer patients in clinical trials need not be precise, in: Symington T, Williams AB, McVie JG (eds): Cancer: Assessment and Monitoring. Edinburgh, Chruchill Livingstone, 1980, pp 377-381

Handedness and Carotid Plaque Lesion Since Fisher's first description in 19511 of the relation between stroke risk and extracranial carotid stenosis, there have been several studies of the hierarchy of this risk with increasing severity of the carotid lesion.2'3 However, the relation between handedness, carotid artery disease, and neuroplasticity has not been given attention. I report here what I believe to be an indication that there may be an association between handedness and carotid artery disease.

Handedness and carotid plaque lesion.

Letters to the Editor K. Asplund Department of Medicine University Hospital Umea, Sweden G. Boysen Department of Neurology Rigshospitalet Copenhagen,...
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