Symptom dimensions stability over time in recent onset psychosis: A prospective study.
Dedifferentiation
Differentiation
Factor structure
PANSS
Psychosis
Schizophrenia
Journal
Schizophrenia research
ISSN: 1573-2509
Titre abrégé: Schizophr Res
Pays: Netherlands
ID NLM: 8804207
Informations de publication
Date de publication:
08 2022
08 2022
Historique:
received:
30
11
2021
revised:
16
06
2022
accepted:
19
06
2022
pubmed:
2
7
2022
medline:
19
8
2022
entrez:
1
7
2022
Statut:
ppublish
Résumé
The factorial structure of schizophrenia symptoms has been much debated but little is known on its degree of unicity, specificity as well as its dynamic over time. Symptom differentiation is a phenomenon according to which patients' symptoms could differentiate from one another during illness to form more independent, distinct dimensions. On the contrary, symptom dedifferentiation is an increase in the correlations between those symptoms over time. The goal of this study was to investigate symptom differentiation or dedifferentiation over time in recent onset psychosis using the Positive and Negative Syndrome Scale. A confirmatory factor analysis model based on the consensus five-factor model of the Positive and Negative Syndrome Scale for schizophrenia was estimated on seven different time points over a three-year period. A general factor capturing common variance between every symptom was also included. Explained common variance was computed for the general factor and each specific factor. Three hundred and sixty-two recent onset psychosis patients were assessed. Results showed no evidence for either symptom differentiation or dedifferentiation over time. Specific symptoms accounted for >70 % of the variance suggesting a high degree of specificity of the symptomatology. Overall, this study adds support for a highly multidimensional approach to clinical symptom assessment with an explicit focus on depression. The premise behind the staging approach being inherently one-dimensional, implications for further research is discussed.
Sections du résumé
BACKGROUND
The factorial structure of schizophrenia symptoms has been much debated but little is known on its degree of unicity, specificity as well as its dynamic over time. Symptom differentiation is a phenomenon according to which patients' symptoms could differentiate from one another during illness to form more independent, distinct dimensions. On the contrary, symptom dedifferentiation is an increase in the correlations between those symptoms over time. The goal of this study was to investigate symptom differentiation or dedifferentiation over time in recent onset psychosis using the Positive and Negative Syndrome Scale.
METHODS
A confirmatory factor analysis model based on the consensus five-factor model of the Positive and Negative Syndrome Scale for schizophrenia was estimated on seven different time points over a three-year period. A general factor capturing common variance between every symptom was also included. Explained common variance was computed for the general factor and each specific factor.
RESULTS
Three hundred and sixty-two recent onset psychosis patients were assessed. Results showed no evidence for either symptom differentiation or dedifferentiation over time. Specific symptoms accounted for >70 % of the variance suggesting a high degree of specificity of the symptomatology.
CONCLUSIONS
Overall, this study adds support for a highly multidimensional approach to clinical symptom assessment with an explicit focus on depression. The premise behind the staging approach being inherently one-dimensional, implications for further research is discussed.
Identifiants
pubmed: 35777150
pii: S0920-9964(22)00254-7
doi: 10.1016/j.schres.2022.06.019
pii:
doi:
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
126-131Informations de copyright
Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.