Center for Clinical Epidemiology and Biostatistics, Center for Pharmacoepidemiology Research and Training, Department of Biostatistics, Epidemiology, and Informatics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States of America.
Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia, PA, United States of America.
PLoS One. 2020 Feb 5;15(2):e0228471. doi: 10.1371/journal.pone.0228471. eCollection 2020.
Stigma around hepatitis C virus (HCV) infection is an important and understudied barrier to HCV prevention, treatment, and elimination. To date, no validated instrument exists to measure patients' experiences of HCV stigma. This study aimed to revise the Berger (2001) HIV stigma scale and evaluate its psychometric properties among patients with HCV infection.
The Berger HIV stigma scale was revised to ask about HCV and administered to patients with HCV (n = 270) in Philadelphia, Pennsylvania. Scale reliability was evaluated as internal consistency by calculating Cronbach's alpha. Exploratory factor analysis was performed to evaluate construct validity by comparing item clustering to the Berger HIV stigma scale subscales. Item response theory was employed to further evaluate individual items and to calibrate items for simulated computer adaptive testing sessions in order to identify potential shortened instruments.
The revised HCV Stigma Scale was found to have good reliability (α = 0.957). After excluding items for low loadings, the exploratory factor analysis indicated good construct validity with 85% of items loading on pre-defined factors. Analyses strongly suggested the predominance of an underlying unidimensional factor solution, which yielded a 33-item scale after items were removed for low loading and differential item functioning. Adaptive simulations indicated that the scale could be substantially shortened without detectable information loss.
The 33-item HCV Stigma Scale showed sufficient reliability and construct validity. We also conducted computer adaptive testing simulations and identified shortened six- and three-item scale alternatives that performed comparably to the original 40-item scale.
丙型肝炎病毒（HCV）感染相关污名是 HCV 预防、治疗和消除的一个重要而研究不足的障碍。迄今为止，尚无经过验证的工具可用于衡量患者的 HCV 污名体验。本研究旨在修订 Berger（2001）HIV 污名量表，并评估其在 HCV 感染患者中的心理测量特性。
对 Berger HIV 污名量表进行修订，以询问 HCV 相关问题，并在宾夕法尼亚州费城的 HCV 患者（n=270）中进行评估。通过计算 Cronbach's alpha 评估量表的可靠性，即内部一致性。通过将项目聚类与 Berger HIV 污名量表的亚量表进行比较，进行探索性因素分析，以评估结构效度。采用项目反应理论进一步评估各个项目，并对模拟计算机自适应测试的项目进行校准，以确定潜在的简化工具。
修订后的 HCV 污名量表具有良好的可靠性（α=0.957）。在排除低负荷的项目后，探索性因素分析表明，具有良好的结构效度，85%的项目符合预定义的因子。分析强烈表明存在一个潜在的单一维度因子解决方案，在去除低负荷和不同项目功能的项目后，得到一个 33 项的量表。自适应模拟表明，在没有明显信息损失的情况下，该量表可以大大缩短。
33 项 HCV 污名量表具有足够的可靠性和结构效度。我们还进行了计算机自适应测试模拟，并确定了简化的六和三项目量表替代方案，它们与原始的 40 项量表表现相当。
