The Korean Version of the Schizophrenia Cognition Rating Scale: Reliability and Validity

OBJECTIVE: This study's aim was to develop and standardize a Korean version (SCoRS-K) of the Schizophrenia Cognition Rating Scale (SCoRS), which is used to evaluate the degree of cognitive dysfunction affecting the everyday functioning of people with schizophrenia. METHODS: Eighty-four schizophrenia patients with stable symptoms who were receiving outpatient treatment and rehabilitation therapy, and 29 demographically matched non-patient controls, participated in the study. Demographic data were collected, and clinical symptoms, cognitive function, and social function were evaluated to verify SCoRS-K's reliability and validity. Clinical symptoms were evaluated using the Positive and Negative Syndrome Scale and the Clinical Global Impression-Schizophrenia Scale. Cognitive function was evaluated using a short form of the Korean Wechsler Adult Intelligence Scale and the Wisconsin Card Sorting Test (WCST). Social function was evaluated using the Social and Occupational Functioning Assessment Scale, the Schizophrenia Quality of Life Scale, and the Social Functioning Scale. RESULTS: Data analysis demonstrated SCoRS-K's statistically significant reliability and validity. SCoRS-K has high internal consistency (Cronbach's alpha; patient 0.941, informant 0.905, interviewer 0.964); test-retest reliability [patient 0.428 (p=0.003), informant 0.502 (p<0.001), interviewer 0.602 (p<0.001); and global rating 0.642 (p<0.001)]. The mean scores of subjects were significantly higher than those of the controls (p<0.001), demonstrating SCoRS-K's discriminant validity. Significant correlations between the total scores and global rating score of SCoRS-K and those of the scales and tests listed above (except WCST) support SCoRS-K's concurrent validity. CONCLUSION: SCoRS-K is a useful instrument for evaluating the degree of cognitive dysfunction in Korean schizophrenia patients.

The Korean Version of the University of California San Diego Performance-based Skills Assessment: Reliability and Validity

OBJECTIVE: The study’s aim was to develop and standardize a Korean version of the University of California San Diego Performance-based Skills Assessment (K-UPSA), which is used to evaluate the daily living function of patients with schizophrenia. METHODS: Study participants were 78 patients with schizophrenia and 27 demographically matched healthy controls. We evaluated the clinical states and cognitive functions to verify K-UPSA’s reliability and validity. For clinical states, the Positive and Negative Syndrome Scale, Clinical Global Impression-Schizophrenia scale, and Social and Occupational Functioning Assessment Scale and Schizophrenia Quality of Life Scale-fourth revision were used. The Schizophrenia Cognition Rating Scale, Short-form of Korean-Wechsler Adult Intelligence Scale, and Wisconsin Card Sorting Test were used to assess cognitive function. RESULTS: The K-UPSA had statistically significant reliability and validity. The K-UPSA has high internal consistency (Cronbach’s alpha, 0.837) and test-retest reliability (intra-class correlation coefficient, 0.381–0.792; p<0.001). The K-UPSA had significant discriminant validity (p<0.001). Significant correlations between the K-UPSA’s scores and most of the scales and tests listed above demonstrated K-UPSA’s concurrent validity (p<0.001). CONCLUSION: The K-UPSA is useful to evaluate the daily living function in Korean patients with schizophrenia.

The Relationship between Language Ability and Cognitive Function in Patients with Schizophrenia

OBJECTIVE: Cognitive dysfunction is common in people with schizophrenia, and language disability is one of the most notable cognitive deficits. This study assessed the use and comprehension ability of the Korean language in patients with schizophrenia and the correlations between language ability and cognitive function. METHODS: Eighty-six patients with schizophrenia and a group of 29 healthy controls were recruited. We assessed both clinical symptoms and cognitive functions including Korean language ability. For clinical symptoms, the Positive and Negative Syndrome Scale, Clinical Global Impression-Schizophrenia Scale, and Social and Occupational Functioning Assessment Scale were used. For the Korean language ability assessment, a portion of the Korean Broadcasting System (KBS) Korean Language Test was used. The Short-form of Korean-Wechsler Adult Intelligence Scale, the Korean version of the University of California San Diego (UCSD) Performance-based Skills Assessment (K-UPSA), and the Wisconsin Card Sorting Test (WCST) were used to assess cognitive functions. RESULTS: Schizophrenic patients had significantly lower scores in the language and cognitive function tests both in the total and subscale scores. Various clinical scores had negative correlations with reading comprehension ability of the KBS Korean Language Test. The WCST and a part of the K-UPSA had positive correlations with multiple domains of the language test. CONCLUSION: A significant difference was found between schizophrenic patients and controls in language ability. Correlations between Korean language ability and several clinical symptoms and cognitive functions were demonstrated in patients with schizophrenia. Tests of cognitive function had positive correlations with different aspects of language ability.

Association of Antipsychotic-Induced QTc Prolongation with 5-HTTLPR

OBJECTIVE: A Comparison of QTc prolongation for various antipsychotics and an analysis of QTc prolongation for the various types of serotonin transporter polymorphism were performed. METHOD: EKG was checked, followed by QTc measurement as Bazett's correction, and the serotonin transporter polymorphism was examined in 110 chronic schizophrenia patients were performed EKG before 24 weeks ago. We defiened QTc prolongation as over 450ms. The risk factor of sudden cardiac death were defiend as QTc prolongation and or 60ms in delta value. RESULT: The prevalence of QTc prolongation in this study was 7.3%, and the prevalence of over 60ms was 4.5%. Patients who had the risk factors were 10(9.1%). 6/52 who prescribed atypical antipsychotics and 2/58 who prescribed haloperidol showed QTc prolongation. The prevalence who had the risk factor of sudden cardiac death were 16% in atypical antipsychotics group, 3.4% in haloperidol group. QTc prolongation were observed more frequently in l/l type than s/s type. l allele frequency were 50% in QTc prolongated group, 19% in not prolongated group. l allele had an association with QTc prolongation(p<0.01). CONCLUSION: The prevalence of QTc prolongatin was frequent in chronic schizophrenia patients who were prescribed atypical antipsychotics. It has strong association with l allele of 5-HTTLPR.