Xin-Rong Ma1, Cai-Lan Hou2, Yu Zang3, Fu-Jun Jia4, Yong-Qiang Lin2, Yan Li5, Helen F K Chiu5, Gabor S Ungvari6, Christoph U Correll7, Kelly Y C Lai5, Bao-Liang Zhong5, Xiao-Lan Cao5, Mei-Ying Cai8, Jun Yun8, Yu-Tao Xiang9. 1. Southern Medical University, Guangdong Province, China; Guangdong Mental Health Center, Guangdong General Hospital & Guangdong Academy of Medical Sciences, Guangdong Province, China; Ningxia Mental Health Center, Ningxia Ning-An Hospital, Ningxia Province, China. 2. Guangdong Mental Health Center, Guangdong General Hospital & Guangdong Academy of Medical Sciences, Guangdong Province, China. 3. Shenzhen Institute of Mental Health, Shenzhen Kangning Hospital & Shenzhen Mental Health Center, Shenzhen, China. 4. Guangdong Mental Health Center, Guangdong General Hospital & Guangdong Academy of Medical Sciences, Guangdong Province, China. Electronic address: jiafujun@126.com. 5. Department of Psychiatry, Chinese University of Hong Kong, Hong Kong, China. 6. The University of Notre Dame Australia/Marian Centre, Perth, Australia. 7. Division of Psychiatry Research, The Zucker Hillside Hospital, North Shore-Long Island Jewish Health System, Glen Oaks, NY, USA. 8. Guangzhou Yuexiu Center for Disease Control and Prevention, Guangdong Province, China. 9. Faculty of Health Sciences, University of Macau, Macao. Electronic address: xyutly@gmail.com.
Abstract
BACKGROUND: Developing accurate and time-efficient tools to measure depressive symptoms in schizophrenia is important for research and clinical practice. This study tested the psychometric properties of the Chinese version of the 16-item Quick Inventory of Depressive Symptomatology (QIDS-SR) in depressed schizophrenia patients. METHODS: This study included 337 clinically stable patients with schizophrenia. The severity of depressive symptoms was assessed using the Montgomery-Asberg Depression Rating Scale (MADRS), QIDS-SR at baseline and 2 weeks later. Negative symptoms and extrapyramidal symptoms were measured with the negative symptom score of Brief Psychiatric Rating Scale (BPRS) and the Simpson-Angus Scale of Extrapyramidal Symptoms (SAS), respectively. RESULTS: Internal consistency (Cronbach׳s alpha) was 0.73 and 0.67 for QIDS-SR at the baseline and endpoint, respectively. The intra-class correlation coefficient (ICC) for test-retest reliability over the two weeks was 0.77. Two domains (involvement and energy) at baseline and one domain (energy) at endpoint had the highest item-total correlations. The QIDS-SR total score was significantly correlated with the MADRS total score at baseline (r=0.44, p<0.01). Weak correlations of the QIDS-SR score with the scores of the BPRS negative (r=0.18) and the SAS (r=0.05) indicate good discriminant validity. The QIDS-SR showed unidimensional measurement properties in exploratory factor analysis at both baseline. The main limitation of the study is that only clinically stable schizophrenia patients were included. CONCLUSIONS: The QIDS-SR has acceptable psychometric properties in stable schizophrenia patients and may be useful in both research and clinical practice.
BACKGROUND: Developing accurate and time-efficient tools to measure depressive symptoms in schizophrenia is important for research and clinical practice. This study tested the psychometric properties of the Chinese version of the 16-item Quick Inventory of Depressive Symptomatology (QIDS-SR) in depressed schizophreniapatients. METHODS: This study included 337 clinically stable patients with schizophrenia. The severity of depressive symptoms was assessed using the Montgomery-Asberg Depression Rating Scale (MADRS), QIDS-SR at baseline and 2 weeks later. Negative symptoms and extrapyramidal symptoms were measured with the negative symptom score of Brief Psychiatric Rating Scale (BPRS) and the Simpson-Angus Scale of Extrapyramidal Symptoms (SAS), respectively. RESULTS: Internal consistency (Cronbach׳s alpha) was 0.73 and 0.67 for QIDS-SR at the baseline and endpoint, respectively. The intra-class correlation coefficient (ICC) for test-retest reliability over the two weeks was 0.77. Two domains (involvement and energy) at baseline and one domain (energy) at endpoint had the highest item-total correlations. The QIDS-SR total score was significantly correlated with the MADRS total score at baseline (r=0.44, p<0.01). Weak correlations of the QIDS-SR score with the scores of the BPRS negative (r=0.18) and the SAS (r=0.05) indicate good discriminant validity. The QIDS-SR showed unidimensional measurement properties in exploratory factor analysis at both baseline. The main limitation of the study is that only clinically stable schizophreniapatients were included. CONCLUSIONS: The QIDS-SR has acceptable psychometric properties in stable schizophreniapatients and may be useful in both research and clinical practice.
Authors: Tyler B Grove; Ivy F Tso; Jinsoo Chun; Savanna A Mueller; Stephan F Taylor; Vicki L Ellingrod; Melvin G McInnis; Patricia J Deldin Journal: Psychiatry Res Date: 2016-06-25 Impact factor: 3.222