TY - JOUR
T1 - Lack of a bimodal distribution of ventricular size in schizophrenia
T2 - A Gaussian mixture analysis of 1056 cases and controls
AU - Daniel, David G.
AU - Goldberg, Terry E.
AU - Gibbons, Robert D.
AU - Weinberger, Daniel R.
PY - 1991/11/1
Y1 - 1991/11/1
N2 - The finding of clinical and laboratory differences between schizophrenic patients with large and small cerebral ventricles has led to the widespread assumption that large ventricles are a marker that characterizes a subgroup of patients with schizophrenia. We reviewed all published English language ventricle-to-brain ratio (VBR) studies in which individual data points were available (schizophrenics: n = 691, medical controls: n = 205, normal volunteers: n = 160). Using a univariate normal mixture model to examine the distribution of ventricular size in each group, we found no evidence of a mixture of Gaussian distributions (i.e., "bimodality") within any of the three groups. The same analysis was then performed on the combined sample of schizophrenic patients and normal and medical controls, respectively. In each case the improvement in fit of a mixture of normal distributions compared to a single component normal distribution was significant. The data do not support the notion that ventricular enlargement is a discontinuous marker of a subtype of schizophrenia.
AB - The finding of clinical and laboratory differences between schizophrenic patients with large and small cerebral ventricles has led to the widespread assumption that large ventricles are a marker that characterizes a subgroup of patients with schizophrenia. We reviewed all published English language ventricle-to-brain ratio (VBR) studies in which individual data points were available (schizophrenics: n = 691, medical controls: n = 205, normal volunteers: n = 160). Using a univariate normal mixture model to examine the distribution of ventricular size in each group, we found no evidence of a mixture of Gaussian distributions (i.e., "bimodality") within any of the three groups. The same analysis was then performed on the combined sample of schizophrenic patients and normal and medical controls, respectively. In each case the improvement in fit of a mixture of normal distributions compared to a single component normal distribution was significant. The data do not support the notion that ventricular enlargement is a discontinuous marker of a subtype of schizophrenia.
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U2 - 10.1016/0006-3223(91)90003-5
DO - 10.1016/0006-3223(91)90003-5
M3 - Article
C2 - 1747437
AN - SCOPUS:0025934894
SN - 0006-3223
VL - 30
SP - 887
EP - 903
JO - Biological psychiatry
JF - Biological psychiatry
IS - 9
ER -