
Structure and Course of Positive and Negative Symptoms in Schizophrenia
William W. Eaton, PhD;
R. Thara, MD;
Belle Federman;
Beth Melton, ScM;
Kung-yee Liang, PhD
Arch Gen Psychiatry. 1995;52(2):127-134.
Abstract
 |  |
Background This article focuses on the underlying structure and temporal course of the symptoms of schizophrenia.
Methods Ratings of symptoms in 90 schizophrenic patients were made each month for 10 years following the first hospitalization. The analytic methods consisted of cross-tabulation, dichotomous factor analysis, and bivariate dichotomous time series.
Results The factor analyses revealed positive and negative factors with a slight tendency to merge over time. The prevalence of positive and negative symptoms declined in the year following first hospitalization and was stable thereafter. Positive and negative symptoms in 1 month were highly predictive of the same type of symptoms in the next month. Neither type of symptom was strongly associated with the other type in the following month when both types were included in the model. The predictability of the process increased with time.
Conclusions With a few minor caveats, the results suggest that the positive and negative symptom clusters are independent, both cross-sectionally and longitudinally.
Author Affiliations
From the Departments of Mental Hygiene (Dr Eaton and Ms Federman) and Biostatistics (Dr Liang and Ms Melton), School of Hygiene and Public Health, The Johns Hopkins University, Baltimore, Md; and the Schizophrenia Research Foundation, Madras, India (Dr Thara).
CiteULike Connotea Del.icio.us Digg Reddit Technorati Twitter
What's this?
THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES
 |
Beyond the critical period: longitudinal study of 8-year outcome in first-episode non-affective psychosis
Crumlish et al.
Br. J. Psychiatry 2009;194:18-24.
ABSTRACT
| FULL TEXT
Long-acting risperidone improves negative symptoms in stable psychotic patients
Curtis et al.
J Psychopharmacol 2008;22:254-261.
ABSTRACT
Questioning an Axiom: Better Prognosis for Schizophrenia in the Developing World?
Cohen et al.
Schizophr Bull 2008;34:229-244.
ABSTRACT
| FULL TEXT
Longitudinal follow-up in acute and transient psychotic disorders and schizophrenia
Pillmann and Marneros
Br. J. Psychiatry 2005;187:286-287.
ABSTRACT
| FULL TEXT
First-Episode Psychosis: Psychopathology, Quality of Life, and Functional Outcome
Malla and Payne
Schizophr Bull 2005;31:650-671.
ABSTRACT
| FULL TEXT
Empirical Validation of Primary Negative Symptoms: Independence From Effects of Medication and Psychosis
Kelley et al.
Am. J. Psychiatry 1999;156:406-411.
ABSTRACT
| FULL TEXT
A Follow-up Magnetic Resonance Imaging Study of Schizophrenia: Relationship of Neuroanatomical Changes to Clinical and Neurobehavioral Measures
Gur et al.
Arch Gen Psychiatry 1998;55:145-152.
ABSTRACT
| FULL TEXT
|