Toussaint Anne, Kroenke Kurt, Baye Fitsum, Lourens Spencer
Department of Psychosomatic Medicine and Psychotherapy, University Medical Center Hamburg-Eppendorf and Schön Klinik Hamburg Eilbek, Hamburg, Germany.
VA HSR&D Center for Health Information and Communication, Roudebush VA Medical Center, Indianapolis, IN, United States; Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, United States; Regenstrief Institute, Inc., Indianapolis, IN, United States.
J Psychosom Res. 2017 Oct;101:44-50. doi: 10.1016/j.jpsychores.2017.08.002. Epub 2017 Aug 2.
The Patient Health Questionnaire - 15 (PHQ-15) and the Somatic Symptom Scale - 8 (SSS-8) are self-report measures which assess somatic symptom burden. The present study investigates whether the two measures are comparable in terms of their psychometric properties and estimates of symptom burden.
Item characteristics, reliability, symptom severity and construct validity with regard to other relevant psychological, health-related quality of life and disability measures were compared for the PHQ-15m and the SSS-8 in 294 primary care patients who participated in a randomized comparative effectiveness trial targeting pain and mood symptoms.
The reliabilities of the PHQ-15m and the SSS-8 were α=0.66 and α=0.72, respectively. Both measures were highly correlated (r=0.79). All item characteristics were comparable and both instruments showed the same pattern of correlations with instruments measuring depression, anxiety, pain, quality of life and impairment (r=0.25 to 0.53). A 1-point score increase (worsening of somatic symptoms) on either instrument resulted in a 3.7% to 3.9% increase in the number of disability days reported for the last four weeks. Using the same severity thresholds (5: low, 10: medium, 15: high), both measures identified nearly identical subgroups of patients with regard to health-related quality of life and disability.
The PHQ-15m and the SSS-8 are comparable measures in terms of reliability and validity and severity classifications. These findings are in line with previous results and support the use of the SSS-8 as a valuable and short alternative to the original PHQ-15 in settings with limited assessment time.
患者健康问卷-15（PHQ-15）和躯体症状量表-8（SSS-8）是评估躯体症状负担的自我报告量表。本研究调查这两种量表在心理测量特性和症状负担估计方面是否具有可比性。
对参与一项针对疼痛和情绪症状的随机对照有效性试验的294名初级保健患者，比较了PHQ-15m和SSS-8在项目特征、信度、症状严重程度以及与其他相关心理、健康相关生活质量和残疾测量指标的结构效度。
PHQ-15m和SSS-8的信度分别为α=0.66和α=0.72。两种量表高度相关（r=0.79）。所有项目特征具有可比性，且两种工具与测量抑郁、焦虑、疼痛、生活质量和功能损害的工具显示出相同的相关模式（r=0.25至0.53）。任一量表上1分的增加（躯体症状加重）导致过去四周报告的残疾天数增加3.7%至3.9%。使用相同的严重程度阈值（5：低，10：中，15：高），两种量表在与健康相关生活质量和残疾方面识别出几乎相同的患者亚组。
PHQ-15m和SSS-8在信度、效度和严重程度分类方面具有可比性。这些发现与先前结果一致，并支持在评估时间有限的情况下，将SSS-8作为原始PHQ-15的一种有价值的简短替代工具使用。
