Objective: To analyze the correlation between quality of life, symptoms, and cognition assessed by the interview-based Schizophrenia Cognition Rating Scale (SCoRS). Methods: Seventy-nine outpatients diagnosed with schizophrenia were evaluated with the Quality of Life Scale – Brazilian version (QLS-BR), the SCoRS, and symptoms scales (Positive and Negative Syndrome Scale [PANSS]). After determining the potential explanatory variables using Spearman’s correlation and Student’s t test results, we ran simple, multivariate, and decision-tree regression analyses to assess the impact of SCoRS and PANSS ratings on mean overall quality of life. Results: Cognitive deficits and negative symptoms were the best predictors of quality of life. A low degree of negative symptoms (PANSS negative < 11) was a strong predictor of better quality of life (QLS ∼ 75), regardless of SCoRS rating. Among participants with more severe negative symptoms, elevated cognitive impairment (interviewer SCoRS ∼ 44) was a predictor of worse quality of life (QLS ∼ 44). Conclusions: Cognitive impairment determined by interview-based assessment seems to be a strong predictor of quality of life in subjects with severe negative symptoms. These results support the usefulness of SCoRS for cognitive assessment that is relevant to the everyday life of patients with schizophrenia.

Resumo A avaliação cognitiva na esquizofrenia tem utilizado tradicionalmente baterias longas e complexas ou que variam significativamente em seu conteúdo. A "Brief Assessment of Cognition in Schizophrenia" (BACS) foi desenvolvida para cobrir os principais déficits cognitivos na esquizofrenia, para ser de fácil e breve aplicação, assim como portátil, sensível e confiável. Objetivos: Investigar a aplicabilidade e a sensibilidade da versão brasileira da BACS (Brazilian-BACS). Métodos: O desempenho de 20 pacientes estáveis com esquizofrenia na Brazilian-BACS foi comparado ao de 20 controles saudáveis pareados. Resultados: A aplicação da Brazilian-BACS exigiu 43.4±8.4 minutos nos pacientes e 40.5±5.7 minutos nos controles (p=0.17). Todos os testes foram significativamente diferentes entre pacientes e controles (P<0.01). A correlação de Pearson e o alfa de Cronbach evidenciaram alto grau de consistência interna no desempenho dos pacientes. O déficit cognitivo nos pacientes foi cerca de 1,5 desvio-padrão menor do que nos controles. Esses resultados são consistentes com os relatados na validação da versão original e em meta-análises de estudos similares. Conclusões: A Brazilian-BACS mostrou boas aplicabilidade e sensibilidade na investigação dos principais domínios cognitivos comprometidos na esquizofrenia. Portanto, a Brazilian-BACS mostra-se um instrumento promissor no estudo da cognição de pacientes com esquizofrenia no Brasil.

Abstract Cognitive assessment in schizophrenia has traditionally used batteries that are long and complex or differ widely in their content. The Brief Assessment of Cognition in Schizophrenia (BACS) has been developed to cover the main cognitive deficits of schizophrenia as well as to be easily and briefly administered, portable, sensitive and reliable. Objectives: To investigate the applicability and sensitivity of the Brazilian Version of the BACS (Brazilian-BACS). Methods: Performance of 20 stable patients with schizophrenia on the Brazilian-BACS was compared to 20 matched healthy controls. Results: Applying the Brazilian-BACS required 43.4±8.4 minutes for patients and 40.5±5.7 minutes for controls (p=0.17). All tests demonstrated significant differences between controls and patients (P<0.01). Pearson's correlation analysis and Cronbach's a evidenced a high internal consistency for patient performance. The cognitive deficit in the patients was approximately 1.5 standard deviations below controls. These results were consistent with those reported in the validation of the original version and in meta-analyses of similar studies. Conclusions: The Brazilian-BACS displayed good applicability and sensitivity in assessing the major cognitive constructs that are impaired in schizophrenia. Thus, the Brazilian-BACS seems to be a promising tool for assessing cognition in patients with schizophrenia in Brazil.