OBJECTIVE: To evaluate the psychometric properties of the PSS, FACIT-Fatigue and pain-VAS using data from Effisayil 1, a randomised trial of spesolimab in patients with moderate-to-severe GPP.
METHODS: Inter-item correlations and confirmatory factor analysis (CFA) were performed using Week 1 data. Internal consistency was assessed with Cronbach\'s α coefficient using baseline and Week 1 data. Test-retest reliability was assessed using intraclass correlation coefficients (ICCs); change data for the GPP Physician Global Assessment total score and pustulation subscore were used to define a stable population. Convergent validity was assessed at baseline and Week 1 using Spearman\'s rank-order correlations. Known-groups validity was measured by analysis of variance using Week 1 data. Ability to detect change from baseline to Week 1 was evaluated by analysis of covariance.
RESULTS: Inter-item and item-to-total correlations were moderate or strong for most PSS and FACIT-Fatigue items. CFA demonstrated the unidimensionality of the PSS and FACIT-Fatigue, with high factor loadings for most items (PSS range, 0.75-0.94; FACIT-Fatigue range, 0.11-0.93) and acceptable fit statistics. Both scores demonstrated internal consistency (Cronbach\'s α, 0.71 and 0.95, respectively). The PSS, FACIT-Fatigue and pain-VAS demonstrated test-retest reliability (ICCs ≥0.70) and good evidence of convergent validity. Furthermore, the PROs could differentiate between known groups of varying symptom severity (range, p < 0.0001-0.0225) and detect changes in symptom severity from baseline to Week 1 (range, p < 0.0001-0.0002).
CONCLUSIONS: Overall, these results support the reliability, validity and ability to detect change of the PSS, FACIT-Fatigue and pain-VAS as PROs in patients with GPP.
目的:为了评估PSS的心理测量学特性,FACIT-疲劳和疼痛-VAS使用来自Effisayil1的数据,该数据是spesolimab在中度至重度GMP患者中的随机试验。
方法:使用第1周数据进行项目间相关性和验证性因素分析(CFA)。使用基线和第1周数据用Cronbach'sα系数评估内部一致性。使用组内相关系数(ICC)评估了重测可靠性;使用了GMP医师全球评估总分和脓疱子得分的变化数据来定义稳定的人群。使用Spearman的等级顺序相关性在基线和第1周评估收敛有效性。通过使用第1周数据的方差分析来测量已知组的有效性。通过协方差分析评估检测从基线到第1周的变化的能力。
结果:对于大多数PSS和FACIT-疲劳项目,项目间和项目与总的相关性是中等或强的。CFA证明了PSS和FACIT-疲劳的一维性,对于大多数项目具有高因子载荷(PSS范围,0.75-0.94;FACIT-疲劳范围,0.11-0.93)和可接受的拟合统计数据。两个分数都表现出内部一致性(Cronbach'sα,分别为0.71和0.95)。PSS,FACIT-疲劳和疼痛-VAS表现出重测可靠性(ICC≥0.70)和收敛有效性的良好证据。此外,PRO可以区分不同症状严重程度的已知组(范围,p<0.0001-0.0225),并检测症状严重程度从基线到第1周的变化(范围,p<0.0001-0.0002)。
结论:总体而言,这些结果支持可靠性,检测PSS变化的有效性和能力,FACIT-疲劳和疼痛-VAS作为GMP患者的PRO。