Desai Nisha S, Poindexter Gabriele B, Monthrope Yvette Miller, Bendeck Sandra E, Swerlick Robert A, Chen Suephy C
Washington University, Saint Louis, Missouri, USA.
J Am Acad Dermatol. 2008 Aug;59(2):234-44. doi: 10.1016/j.jaad.2008.04.006. Epub 2008 Jun 11.
We sought to develop a validated, reliable pruritus-specific quality-of-life (QOL) instrument, ItchyQoL.
From 21 in-depth interviews with patients with pruritus, we developed 22 pruritus-specific items, and hypothesized 3 major constructs that explain the way pruritus affects patients' QOL: symptoms, functional limitations, and emotions. We developed two versions of the pruritus QOL instrument, which assess for level of bother or frequency using items from the interviews and from generic skin QOL instruments, Skindex-16 (bother) and Skindex-29 (frequency). The instrument was tested for validity, reliability, and responsiveness. The frequency version was subsequently applied clinically to further evaluate its face validity.
A total of 89 patients with dermatologic conditions participated in the validation phase and 101 patients participated in the clinical application phase of the study. Construct validity was demonstrated by principal axes factor analyses and by demonstrating that differences in symptoms, functioning, and emotion differed among the varying levels of self-reported pruritus severity more than would be expected by chance (P < .05 by analysis of variance). The instrument demonstrated reliability with internal consistency (Cronbach alpha: frequency 0.72-0.93 and bother 0.78-0.81) and reproducibility (intraclass correlation coefficient: frequency 0.91 and bother 0.84-0.87). The instrument suggested preliminary responsiveness for patients with improved disease for both frequency and bother items with both overall scores and the majority of the subscales scored demonstrating significant changes. Discriminant validity was shown by comparing differences in and the number of insensitive items between the pruritus-specific QOL instrument and the generic Skindex instruments.
Lack of generalizability and potential selection bias are limitations.
This study represents, to our knowledge, the first attempt at a pruritus-specific QOL instrument that is reliable, valid, and responsive.
我们试图开发一种经过验证的、可靠的瘙痒特异性生活质量（QOL）工具——瘙痒生活质量量表（ItchyQoL）。
通过对21名瘙痒患者进行深入访谈，我们制定了22个瘙痒特异性条目，并假设了3个主要结构来解释瘙痒影响患者生活质量的方式：症状、功能限制和情绪。我们开发了两个版本的瘙痒生活质量工具，使用访谈和通用皮肤生活质量工具Skindex - 16（困扰程度）和Skindex - 29（频率）中的条目来评估困扰程度或频率水平。对该工具进行了效度、信度和反应度测试。随后将频率版本应用于临床以进一步评估其表面效度。
共有89名皮肤病患者参与了该研究的验证阶段，101名患者参与了临床应用阶段。主成分因子分析以及自我报告的瘙痒严重程度不同水平之间症状、功能和情绪差异大于随机预期（方差分析P < 0.05）证明了结构效度。该工具在内部一致性（Cronbach α：频率0.72 - 0.93，困扰程度0.78 - 0.81）和可重复性（组内相关系数：频率0.91，困扰程度0.84 - 0.87）方面显示出信度。该工具对病情改善的患者在频率和困扰程度条目上均显示出初步反应度，总体得分和大多数子量表得分均有显著变化。通过比较瘙痒特异性生活质量工具与通用Skindex工具之间不敏感条目的差异和数量，显示出判别效度。
缺乏普遍性和潜在的选择偏倚是局限性。
据我们所知，本研究首次尝试开发一种可靠、有效且有反应度的瘙痒特异性生活质量工具。
