Factor structure of neurologic examination abnormalities in unmedicated schizophrenia.
The heterogeneity and uncertain significance of neurologic exam abnormalities in schizophrenia prompted us to evaluate their factor structure. We administered a modified version of the Neurological Evaluation Scale (NES) to 103 unmedicated patients with schizophrenia. Data were distilled by combining right- and left-side scores, and by eliminating superfluous, rarely abnormal and unreliable items from the analysis. Exploratory principal components analysis yielded four factors: repetitive motor tasks (fist-ring, fist-edge-palm, alternating fist-palm, dysdiadochokinesis); cognitive-perceptual tasks (memory, audiovisual integration, right-left orientation, face-hand test, rhythm tapping reproduction); balancing tasks (Romberg, tandem gait); and the palmomental reflex. Evaluation of the relationship between these factors and clinical and demographic variables revealed a robust correlation between the cognitive-perceptual factor and full-scale IQ score. This analysis is a step toward developing empirical subscales of a modified NES, which may provide insights into the nature of neurologic impairment in schizophrenia and may prove clinically useful.
Sanders
R D
RD
VA Pittsburgh Healthcare System, 151 R, 7180 Highland Drive Division, Pittsburgh, PA 15206-1297, USA.
Keshavan
M S
MS
Forman
S D
SD
Pieri
J N
JN
McLaughlin
N
N
Allen
D N
DN
van Kammen
D P
DP
Goldstein
G
G
D000328:Adult; D002908:Chronic Disease; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D008297:Male; D009460:Neurologic Examination; D012559:Schizophrenia / Q000503:physiopathology*