Validity And Reliability Of The Chinese Version Of Characteristics Of Delusions Rating Scale In Evaluating Delusions With Schizophrenic

Objective:To investigate the reliability and validity of the Chinese version of Characteristics of Delusions Rating Scale (C-CDRS) in evaluating delusions in-schizophrenia patients.Methods:Authorized by the original authors, the English version of CDRS was translated into Chinese. Totally one hundred and thirty-seven inpatients with schizophrenia meeting the criteria of the International Classification of Diseases, tenth version (ICD-10) were included and assessed with the C-CDRS for exploratory factor analysis and internal consistency analysis. The Positive and Negative Syndrome Scale (PANSS) was administered to test the criterion validity. Seventy-three inpatients were re-tested with the C-CDRS one week later for the retest reliability. Forty inpatients were re-evaluation C-CDRS and PANSS after four week’s treatment, testing the effectiveness of C-CDRS in evaluating delusional symptoms.Results:Exploratory factor analysis extracted three common factors, including cognition factor、emotion factor and bizarreness factor and76.45%of variance was explained. The cognition factor include (conviction、preoccupation、interference、 dismissibility、reassurance、pervasiveness). The emotion factor include (resistance、 worry、unhappiness). The bizarreness factor include (absurdity、self-evident).The total scores and three factors of C-CDRS had positive correlation with the delusion point of PANSS (r=0.84、0.88、0.69、0.66,均P<0.01). The total score and three factors of C-CDRS had positive correlation with positive symptoms of PANSS (r=0.67、0.70、 0.57,0.63,均P<0.01). The total score of C-CDRS had positive correlation with the total score of PANSS(r=0.58, P<0.01). The Cronbach’s a coefficient of C-CDRS total score was0.83, the Cronbach’s a coefficient of three common factors were0.84,0.77and0.78. Seventy-three inpatients were re-evaluation with C-CDRS after one week, test the retest reliability of the C-CDRS. The retest correlation coefficient of the total scale of CDRS was0.85(P<0.01). The retest correlation coefficient of three factors were0.86、0.82、0.83(P<0.01). The retest correlation coefficient of eleven entries were between0.72to0.92(P<0.01). Forty patients were re-evaluated with C-CDRS and PANSS after four week’s treatment. The total score of CDRS reduced from (76.32±7.79) to (41.28±3.82). The total score of PANSS reduced from (84.35±9.13) to (42.67±5.74). The difference of C-CDRS and PANSS had significant positive correlation. The pearson correlation coefficient of the less scores of C-CDRS and PANSS was0.82(P<0.01).Conclusion:The Chinese version of Characteristics of Delusions Rating Scale (C-CDRS) is a reliable and valid assessment tool for delusions in schizophrenia patients, and an economical instrument for research practices.