Cedraschi C, Marty M, Courvoisier D S, Foltz V, Mahieu G, Demoulin C, Gierasimowicz Fontana A, Norberg M, de Goumoëns P, Rozenberg S, Genevay S
Division of General Medical Rehabilitation, Geneva University Hospitals, Geneva, Switzerland.
Division of Rheumatology, CHU Henri-Mondor Creteil, Paris, France.
Eur Spine J. 2016 Jan;25(1):265-274. doi: 10.1007/s00586-015-3935-9. Epub 2015 Apr 28.
The Core Outcome Measure Index (COMI) is a multidimensional questionnaire that investigates five dimensions in low back pain (LBP) patients, but does not address the psychological dimension. As the biopsychosocial perspective is recognized as important to capture the entire clinical picture of these patients, this multicenter prospective cohort study was designed to investigate the psychometric properties of a modified version of the COMI (COMIAD) which included 2 additional items, exploring anxiety and depression, respectively.
168 subacute or chronic LBP patients recruited in spine clinics completed a set of questionnaires before and after treatment (follow-up at 6 months). Construct validity was explored by comparing each item of the COMIAD to validated full-length questionnaires. Thus two additional questionnaires were included to assess the construct validity of the anxiety and depression measures. The psychometric properties of the COMI and COMIAD were then compared.
The two new items showed good internal consistency, high correlations with the corresponding full-length questionnaires, no floor or ceiling effect and good reproducibility (test-retest agreement kappa 0.68 for anxiety, 0.62 for depression). The addition of the 2 items did not alter internal validity (Cronbach's alpha = 0.88 and 0.87, respectively). The smallest detectable difference, the Minimal Clinically Important Improvement and the Patient Acceptable Symptom State were only minimally affected by the changes.
The questions exploring anxiety and depression have good intrinsic and psychometric capacities (i.e., no floor or ceiling effects and high correlations with full-length scales) and did not significantly modify the psychometrics of the original COMI questionnaire. The COMIAD offers the possibility to include the psychological dimension in the multidimensional evaluation without significantly affecting questionnaire length.
核心结局指标指数（COMI）是一份多维度问卷，用于调查腰痛（LBP）患者的五个维度，但未涉及心理维度。由于生物心理社会视角被认为对于全面了解这些患者的临床情况很重要，因此本多中心前瞻性队列研究旨在调查COMI的一个修改版本（COMIAD）的心理测量特性，该版本增加了2个项目，分别用于探究焦虑和抑郁。
在脊柱诊所招募的168例亚急性或慢性LBP患者在治疗前后（6个月随访）完成了一组问卷。通过将COMIAD的每个项目与经过验证的全长问卷进行比较来探索结构效度。因此，纳入了另外两份问卷以评估焦虑和抑郁测量的结构效度。然后比较了COMI和COMIAD的心理测量特性。
这两个新项目显示出良好的内部一致性，与相应的全长问卷高度相关，无地板效应或天花板效应，且具有良好的可重复性（焦虑试验 - 重测一致性kappa为0.68，抑郁为0.62）。添加这2个项目并未改变内部效度（Cronbach's alpha分别为0.88和
0.87）。最小可检测差异、最小临床重要改善和患者可接受症状状态仅受到这些变化的轻微影响。
探究焦虑和抑郁的问题具有良好的内在和心理测量能力（即无地板效应或天花板效应，与全长量表高度相关），并且未显著改变原始COMI问卷的心理测量学特性。COMIAD提供了在多维度评估中纳入心理维度的可能性，而不会显著影响问卷长度。
