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Aim: The aim of the study was an evaluation of validity measures of the CASS (Clinical Assessment of Schizophrenic Syndromes)--a new multi-purpose and multi-level clinical diagnostic instrument consisting of a diagnostic questionnaire (CASS-D) allowing to analyze a diagnosis of schizophrenia according to DSM-IV and ICD-10 criteria as well as of three rating scales designed for description and intensity evaluation of schizophrenic syndromes on the global (CASS-G), dimensional (CASS-P, a profile of 13 basic dimensions) or symptomatological (CASS-S, a set of 31 symptoms) level., Subjects: 194 inpatients consecutively admitted to the Department within approximately 6 months were assessed twice (at the start and end of their hospitalization) by 12 trained diagnosticians., Method: Several measures of validity were analyzed. Results obtained by means of CASS were compared with results of the SANS/SAPS, BPRS, and PANSS as reference rating scales (diagnostic validity). Characteristics of frequency, intensity, dynamics and specificity of scale items were used to analyze content validity. Factorial structure of CASS scales was applied as a measure of construct validity., Findings: Diagnostic validity of the new instrument seems to be confirmed by its very high correlation coefficients with rating scales recognized as international standards: BPRS, PANSS, and SANS/SAPS. Reasonable characteristics of frequency, intensity, dynamics and specificity of individual items (dimensions, symptoms) and sum scores of CASS scales and relationships between their values strongly suggest their content validity. Both sum (CASS-P, CASS-S) and global (CASS-G) scores of scales under study revealed some specificity--they had significantly higher values in patients with schizophrenia than in patients with other diagnoses. It allows to distinguish in a schizophrenic syndrome described by CASS components which are specific and not specific for this disorder. The latter have been left also in the final version for their practical and clinical importance. Construct validity of the CASS was studied separately for different scales (CASS-P, CASS-S) and different groups (all or only schizophrenic patients) by means of several factor analyses, and performed along identical statistical procedure (principal component method of extraction with criterion eigenvalue > 1, followed by Equamax rotation). Resulting solutions could be interpreted reasonably and consistently with contemporary attempts to find adequate factorial models of intrinsic structure of schizophrenic syndrome. Thus they support confidence for constructive aspect of the CASS validity., Conclusions: Ultimately, results obtained in the study suggest that the CASS may be considered as an instrument with some promising indices of diagnostic, content and construct validity, which may be potentially useful for clinical and research purposes.

Unlabelled: The CASS (Clinical Assessment of Schizophrenic Syndromes) is a new multi-purpose and multi-level clinical diagnostic instrument consisting of a diagnostic questionnaire (CASS-D) allowing for analysis of a diagnosis of schizophrenia according to DSM-IV and ICD-10 criteria, as well as of three rating scales designed for description and intensity evaluation of schizophrenic syndromes on the global (CASS-G), dimensional (CASS-P, a profile of 13 basic dimensions) or symptomatological (CASS-S, a set of 31 symptoms) level., Aim: The paper presents a rationale and construction principles of the tool followed by a study of its reliability and sensitivity as well as by preliminary attempt to normalize its results., Subjects: Twelve trained diagnosticians assessed twice (at the start and end of their hospitalization) 194 inpatients admitted consecutively, within approximately 6 months, to the Department., Method: Results of the CASS were compared with results of the SANS/SAPS, BPRS, and PANSS assessments playing the role of standard, reference instruments., Findings: High agreement coefficients (kappa) were calculated between a diagnosis of schizophrenia based on unoperationalized (clinical) criteria and operationalized diagnoses based on the CASS diagnostic questionnaire including ICD-10 and DSM-IV diagnostic criteria and algorithms. In the case of both complex (many-item) CASS scales (CASS-P, CASS-S) high reliability measures (internal consistency according to Cronbach's alpha) were found. Characteristics of frequency, intensity and dynamics of the CASS individual symptoms, dimensions and of syndrome as a whole were consistent with expectations based on clinical experience. Direct indices of clinical improvement calculated from CASS-G, CASS-P or CASS-S scores obtained at two time-points (admission, discharge) correlated fairly highly with more direct measures based on diagnosticians' clinical global impressions made when summing the results of treatment at discharge from the hospital. This finding suggests that CASS scores may sensitively register changes in patients' mental state during hospital stay and treatment. On the base of empirical distributions of CASS scales, a normalization (sten-scales) was proposed which may be useful for comparison of results obtained in differing groups of patients. Analysis of percentile and sten distributions of the CASS-P and CASS-S pointed out that patients with a diagnosis of schizophrenia had higher mean scores than patients with other diagnoses. This observation as well as above mentioned reasonableness (consistency with clinical experience) of a picture and dynamics of schizophrenic syndromes revealed in CASS assessments may be treated as preliminary assumptions of its content validity., Conclusions: Results of the study suggest that CASS has satisfactory measures of reliability and sensitiveness. They allow for a preliminary normalization of its scales and prompt to study its validity.

Diagnostic and symptomatological profiles of schizophrenic syndromes diagnosed according to ICD-10 and DSM-IV were compared. For this reason a group of patients fulfilling at least one of these sets of criteria was created and then diagnostic and symptomatological profile was compared between those who fulfilled the ICD-10 and those who fulfilled DSM-IV criteria. 105 inpatients hospitalized in acute phase of their first or one of consecutive episodes were included--102 of them had fulfilled ICD-10, and 90 DSM-IV criteria of schizophrenia. Diagnostic concordance between the two systems of criteria was high (83%). Differentiation of diagnostic profile (i.e. difference between frequency of fulfilling the specific requirements of ICD-10 or DSM-IV criteria) of the symptoms in these two groups was not significant, expert of 6-month criterion of duration of illness, which was significantly less frequently valid in ICD-10 syndromes group. A comparison of symptomatological profiles (i.e. frequency and intensity of symptoms) of schizophrenic syndromes diagnosed by ICD-10 or DSM-IV criteria and described by several rating scales (PANSS, SAPS/SANS, KOSS-S) did not show any significant differences. Results suggested that despite of different ways of defining the schizophrenic syndromes in both diagnostic systems, disorders manifested in the groups of patients created by means of them are very similar in psychopathological picture. This seems to be a significant change in comparison to more prominent differences contrasting the previous versions of the diagnostic systems (i.e. ICD-9 and DSM-III-R).

Basic indices of reliability and validity of a preliminary version of the new tool for "Clinical Assessment of Schizophrenic Syndrome" (CASS) was evaluated. Six experienced psychiatrists working in two teams examined the mental state of 49 patients with clinical diagnosis of schizophrenia, in the majority of them confirmed by the criteria of DSM-IV and ICD-10 (one of the teams examined 25 patients, the other-24). Each diagnostician rated the patients' mental state independently, by means of three-level rating permitted by the CASS-CASS-G (global), CASS-D (dimensions), and CASS-S (symptoms)--as well as by means of BPRS and PANSS scale included in the study as international standard scales for validity testing. Statistical analysis of the results confirmed that the scales under study allow to obtain results which could be characterized, with few minor exceptions, by high concordance coefficients (Kendall's W) high internal consistence coefficients (Cronbach's alpha) and high correlations (as measured both by Pearson's and Kendall's rank correlation coefficients taub) with internationally appreciated standard scales. It suggests reliability and validity of the CASS to the degree which could be considered as encouraging to continue the study on this instrument.

24 patients have been treated with cis(z)-flupenthixol decanoate for 6-12 months. Intramuscular injections were given about every 3 weeks. Before treatment and on each day of injection the mental state was assessed by BPRS and registration of side effects was performed. Blood samples were taken 7 days after each injection and on the last day of the dosage interval. Neuroleptic activity was determined in serum by RRA and expressed in cis(z)-flupenthixol equivalents. The drug level was significantly correlated to the dose. No clear relationship between drug level and clinical results as well as side effects was found. Less pronounced variations of the drug level between subsequent injections resulted in a positive therapeutic response.