Underlying structure of the National Institutes of Health stroke scale: Results of a factor analysis

Patrick Lyden, Mei Lu, Christy Jackson, John Marler, Rashmi Kothari, Thomas G Brott, Justin Zivin

Research output: Contribution to journalArticle

217 Citations (Scopus)

Abstract

Background and Purpose - No stroke scale has been validated as an outcome measure using data from a clinical trial demonstrating a positive therapeutic effect. Therefore, we proposed to use data from the National Institute of Neurological Disorders and Stroke (NINDS) tPA Stroke Trial to determine whether the National Institutes of Health Stroke Scale (NIHSS) was valid in patients treated with tissue plasminogen activator (tPA) and to explore the underlying clinimetric structure of the NIHSS. Methods - We performed an exploratory factor analysis of NIHSS data from Part 1 (n=291) of the NINDS tPA Stroke Trial to derive a hypothesized underlying factor structure. We then performed a confirmatory factor analysis of this structure using NIHSS data from Part 2 of the same trial (n=333). We then tested whether this final factor structure could be found in tPA- and placebo- treated patients serially over time after stroke treatment. Using 3-month outcome data, we tested for an association between the NIHSS and other measures of stroke outcome. Results - The exploratory analysis suggested that there were 2 factors underlying the NIHSS, representing left and right brain function, confirming the content validity of the scale. An alternative structure composed of 4 factors could be derived, with a better goodness of fit: the first 2 factors could represent left brain cortical and motor function, respectively, and the second 2 factors could represent right brain cortical and motor function, respectively. The same factor structures were then found in tPA and placebo patient groups studied serially over time, confirming the exploratory analysis. All 3-month clinical outcomes were associated with each other at subsequent time points, confirming predictive validity. Conclusions - This is the first study of the validity of a stroke scale in patients treated with effective stroke therapy. The NIHSS appeared to be valid in patients with acute stroke and for finding treatment-related differences. The scale was valid when used serially over time after stroke, up to 3 months, and showed good agreement with other measures of outcome.

Original languageEnglish (US)
Pages (from-to)2347-2354
Number of pages8
JournalStroke
Volume30
Issue number11
StatePublished - Nov 1999

Fingerprint

National Institutes of Health (U.S.)
Statistical Factor Analysis
Stroke
Tissue Plasminogen Activator
National Institute of Neurological Disorders and Stroke
Outcome Assessment (Health Care)
Brain
Placebos
Therapeutic Uses

Keywords

  • Cerebrovascular disorders
  • Clinimetrics
  • Factor analysis, statistical
  • Neuropsychological tests

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine
  • Neuroscience(all)

Cite this

Lyden, P., Lu, M., Jackson, C., Marler, J., Kothari, R., Brott, T. G., & Zivin, J. (1999). Underlying structure of the National Institutes of Health stroke scale: Results of a factor analysis. Stroke, 30(11), 2347-2354.

Underlying structure of the National Institutes of Health stroke scale : Results of a factor analysis. / Lyden, Patrick; Lu, Mei; Jackson, Christy; Marler, John; Kothari, Rashmi; Brott, Thomas G; Zivin, Justin.

In: Stroke, Vol. 30, No. 11, 11.1999, p. 2347-2354.

Research output: Contribution to journalArticle

Lyden, P, Lu, M, Jackson, C, Marler, J, Kothari, R, Brott, TG & Zivin, J 1999, 'Underlying structure of the National Institutes of Health stroke scale: Results of a factor analysis', Stroke, vol. 30, no. 11, pp. 2347-2354.
Lyden P, Lu M, Jackson C, Marler J, Kothari R, Brott TG et al. Underlying structure of the National Institutes of Health stroke scale: Results of a factor analysis. Stroke. 1999 Nov;30(11):2347-2354.
Lyden, Patrick ; Lu, Mei ; Jackson, Christy ; Marler, John ; Kothari, Rashmi ; Brott, Thomas G ; Zivin, Justin. / Underlying structure of the National Institutes of Health stroke scale : Results of a factor analysis. In: Stroke. 1999 ; Vol. 30, No. 11. pp. 2347-2354.
@article{d90ef399447f4c94b715e9fb21eff62e,
title = "Underlying structure of the National Institutes of Health stroke scale: Results of a factor analysis",
abstract = "Background and Purpose - No stroke scale has been validated as an outcome measure using data from a clinical trial demonstrating a positive therapeutic effect. Therefore, we proposed to use data from the National Institute of Neurological Disorders and Stroke (NINDS) tPA Stroke Trial to determine whether the National Institutes of Health Stroke Scale (NIHSS) was valid in patients treated with tissue plasminogen activator (tPA) and to explore the underlying clinimetric structure of the NIHSS. Methods - We performed an exploratory factor analysis of NIHSS data from Part 1 (n=291) of the NINDS tPA Stroke Trial to derive a hypothesized underlying factor structure. We then performed a confirmatory factor analysis of this structure using NIHSS data from Part 2 of the same trial (n=333). We then tested whether this final factor structure could be found in tPA- and placebo- treated patients serially over time after stroke treatment. Using 3-month outcome data, we tested for an association between the NIHSS and other measures of stroke outcome. Results - The exploratory analysis suggested that there were 2 factors underlying the NIHSS, representing left and right brain function, confirming the content validity of the scale. An alternative structure composed of 4 factors could be derived, with a better goodness of fit: the first 2 factors could represent left brain cortical and motor function, respectively, and the second 2 factors could represent right brain cortical and motor function, respectively. The same factor structures were then found in tPA and placebo patient groups studied serially over time, confirming the exploratory analysis. All 3-month clinical outcomes were associated with each other at subsequent time points, confirming predictive validity. Conclusions - This is the first study of the validity of a stroke scale in patients treated with effective stroke therapy. The NIHSS appeared to be valid in patients with acute stroke and for finding treatment-related differences. The scale was valid when used serially over time after stroke, up to 3 months, and showed good agreement with other measures of outcome.",
keywords = "Cerebrovascular disorders, Clinimetrics, Factor analysis, statistical, Neuropsychological tests",
author = "Patrick Lyden and Mei Lu and Christy Jackson and John Marler and Rashmi Kothari and Brott, {Thomas G} and Justin Zivin",
year = "1999",
month = "11",
language = "English (US)",
volume = "30",
pages = "2347--2354",
journal = "Stroke",
issn = "0039-2499",
publisher = "Lippincott Williams and Wilkins",
number = "11",

}

TY - JOUR

T1 - Underlying structure of the National Institutes of Health stroke scale

T2 - Results of a factor analysis

AU - Lyden, Patrick

AU - Lu, Mei

AU - Jackson, Christy

AU - Marler, John

AU - Kothari, Rashmi

AU - Brott, Thomas G

AU - Zivin, Justin

PY - 1999/11

Y1 - 1999/11

N2 - Background and Purpose - No stroke scale has been validated as an outcome measure using data from a clinical trial demonstrating a positive therapeutic effect. Therefore, we proposed to use data from the National Institute of Neurological Disorders and Stroke (NINDS) tPA Stroke Trial to determine whether the National Institutes of Health Stroke Scale (NIHSS) was valid in patients treated with tissue plasminogen activator (tPA) and to explore the underlying clinimetric structure of the NIHSS. Methods - We performed an exploratory factor analysis of NIHSS data from Part 1 (n=291) of the NINDS tPA Stroke Trial to derive a hypothesized underlying factor structure. We then performed a confirmatory factor analysis of this structure using NIHSS data from Part 2 of the same trial (n=333). We then tested whether this final factor structure could be found in tPA- and placebo- treated patients serially over time after stroke treatment. Using 3-month outcome data, we tested for an association between the NIHSS and other measures of stroke outcome. Results - The exploratory analysis suggested that there were 2 factors underlying the NIHSS, representing left and right brain function, confirming the content validity of the scale. An alternative structure composed of 4 factors could be derived, with a better goodness of fit: the first 2 factors could represent left brain cortical and motor function, respectively, and the second 2 factors could represent right brain cortical and motor function, respectively. The same factor structures were then found in tPA and placebo patient groups studied serially over time, confirming the exploratory analysis. All 3-month clinical outcomes were associated with each other at subsequent time points, confirming predictive validity. Conclusions - This is the first study of the validity of a stroke scale in patients treated with effective stroke therapy. The NIHSS appeared to be valid in patients with acute stroke and for finding treatment-related differences. The scale was valid when used serially over time after stroke, up to 3 months, and showed good agreement with other measures of outcome.

AB - Background and Purpose - No stroke scale has been validated as an outcome measure using data from a clinical trial demonstrating a positive therapeutic effect. Therefore, we proposed to use data from the National Institute of Neurological Disorders and Stroke (NINDS) tPA Stroke Trial to determine whether the National Institutes of Health Stroke Scale (NIHSS) was valid in patients treated with tissue plasminogen activator (tPA) and to explore the underlying clinimetric structure of the NIHSS. Methods - We performed an exploratory factor analysis of NIHSS data from Part 1 (n=291) of the NINDS tPA Stroke Trial to derive a hypothesized underlying factor structure. We then performed a confirmatory factor analysis of this structure using NIHSS data from Part 2 of the same trial (n=333). We then tested whether this final factor structure could be found in tPA- and placebo- treated patients serially over time after stroke treatment. Using 3-month outcome data, we tested for an association between the NIHSS and other measures of stroke outcome. Results - The exploratory analysis suggested that there were 2 factors underlying the NIHSS, representing left and right brain function, confirming the content validity of the scale. An alternative structure composed of 4 factors could be derived, with a better goodness of fit: the first 2 factors could represent left brain cortical and motor function, respectively, and the second 2 factors could represent right brain cortical and motor function, respectively. The same factor structures were then found in tPA and placebo patient groups studied serially over time, confirming the exploratory analysis. All 3-month clinical outcomes were associated with each other at subsequent time points, confirming predictive validity. Conclusions - This is the first study of the validity of a stroke scale in patients treated with effective stroke therapy. The NIHSS appeared to be valid in patients with acute stroke and for finding treatment-related differences. The scale was valid when used serially over time after stroke, up to 3 months, and showed good agreement with other measures of outcome.

KW - Cerebrovascular disorders

KW - Clinimetrics

KW - Factor analysis, statistical

KW - Neuropsychological tests

UR - http://www.scopus.com/inward/record.url?scp=0032700790&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0032700790&partnerID=8YFLogxK

M3 - Article

C2 - 10548669

AN - SCOPUS:0032700790

VL - 30

SP - 2347

EP - 2354

JO - Stroke

JF - Stroke

SN - 0039-2499

IS - 11

ER -