Validity of Simpson-Angus Scale (SAS) in a naturalistic schizophrenia population.
BMC Neurol
; 5(1): 5, 2005 Mar 17.
Article
em En
| MEDLINE
| ID: mdl-15774006
ABSTRACT
BACKGROUND:
Simpson-Angus Scale (SAS) is an established instrument for neuroleptic-induced parkinsonism (NIP), but its statistical properties have been studied insufficiently. Some shortcomings concerning its content have been suggested as well. According to a recent report, the widely used SAS mean score cut-off value 0.3 of for NIP detection may be too low. Our aim was to evaluate SAS against DSM-IV diagnostic criteria for NIP and objective motor assessment (actometry).METHODS:
Ninety-nine chronic institutionalised schizophrenia patients were evaluated during the same interview by standardised actometric recording and SAS. The diagnosis of NIP was based on DSM-IV criteria. Internal consistency measured by Cronbach's alpha, convergence to actometry and the capacity for NIP case detection were assessed.RESULTS:
Cronbach's alpha for the scale was 0.79. SAS discriminated between DSM-IV NIP and non-NIP patients. The actometric findings did not correlate with SAS. ROC-analysis yielded a good case detection power for SAS mean score. The optimal threshold value of SAS mean score was between 0.65 and 0.95, i.e. clearly higher than previously suggested threshold value.CONCLUSION:
We conclude that SAS seems a reliable and valid instrument. The previously commonly used cut-off mean score of 0.3 has been too low resulting in low specificity, and we suggest a new cut-off value of 0.65, whereby specificity could be doubled without loosing sensitivity.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Esquizofrenia
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Transtornos Parkinsonianos
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Testes Neuropsicológicos
Tipo de estudo:
Diagnostic_studies
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Prognostic_studies
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Screening_studies
Limite:
Adolescent
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Adult
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Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Ano de publicação:
2005
Tipo de documento:
Article