Abstract：
The Food Allergy Quality of Life Questionnaire-Parent Form (FAQLQ-PF) is a commonly used patient-reported outcome measure in food allergy (FA) research. It was developed before FA treatment clinical trials were commonplace and is used as a secondary outcome measure in pivotal FA treatment trials. We examined the psychometric properties of the FAQLQ-PF and its relevance to children with peanut allergy engaged in an epicutaneous immunotherapy (EPIT) clinical trial.
Analysis was performed on 26 universally answered items of the FAQLQ-PF, from assessments undertaken during the phase 3 PEPITES study (baseline, Month 12), which examined the safety and efficacy of EPIT for children with peanut allergy aged 4-11 years. Item response theory (IRT) was used to assess psychometric parameters of the FAQLQ-PF (i.e., discrimination, difficulty, and information). Confirmatory factor analysis was also employed; reliability was assessed using McDonald\'s omega (ω) and Cronbach\'s alpha (α).
A total of 23 of 26 items presented very high discrimination levels (>1.7), and all 26 fell within the recommended difficulty threshold (between -1.5 and 1.5). The items contributed a reasonable information level for their respective factors/subdomains. The measure also presented a marginally acceptable model fit for the 3-factor structure (e.g., comparative fit index = 0.88, Tucker-Lewis index = 0.87) and good reliability levels across time points (ω and α > 0.90).
Herein, we present a novel reanalysis of the FAQLQ-PF items using IRT. The longitudinal performance of individual items and subscales was corroborated, and items with the highest discrimination were identified, showing that the tool is suitable for longitudinal measurements in FA treatment trials.
Analysis was performed on 26 universally answered items of the FAQLQ-PF, from assessments undertaken during the phase 3 PEPITES study (baseline, Month 12), which examined the safety and efficacy of EPIT for children with peanut allergy aged 4-11 years. Item response theory (IRT) was used to assess psychometric parameters of the FAQLQ-PF (i.e., discrimination, difficulty, and information). Confirmatory factor analysis was also employed; reliability was assessed using McDonald\'s omega (ω) and Cronbach\'s alpha (α).
A total of 23 of 26 items presented very high discrimination levels (>1.7), and all 26 fell within the recommended difficulty threshold (between -1.5 and 1.5). The items contributed a reasonable information level for their respective factors/subdomains. The measure also presented a marginally acceptable model fit for the 3-factor structure (e.g., comparative fit index = 0.88, Tucker-Lewis index = 0.87) and good reliability levels across time points (ω and α > 0.90).
Herein, we present a novel reanalysis of the FAQLQ-PF items using IRT. The longitudinal performance of individual items and subscales was corroborated, and items with the highest discrimination were identified, showing that the tool is suitable for longitudinal measurements in FA treatment trials.
摘要：
食物过敏生活质量问卷-家长表格（FAQLQ-PF）是食物过敏（FA）研究中常用的患者报告结果指标。它是在FA治疗临床试验司空见惯之前开发的，并在关键的FA治疗试验中用作次要结果指标。我们研究了FAQLQ-PF的心理测量特性及其与参与表皮免疫疗法（EPIT）临床试验的花生过敏儿童的相关性。
对FAQLQ-PF的26个普遍回答的项目进行了分析，根据在第三阶段PEPITES研究期间进行的评估(基线，第12个月)，研究了EPIT对4-11岁花生过敏儿童的安全性和有效性。项目反应理论(IRT)用于评估FAQLQ-PF的心理测量参数(即，歧视,困难,和信息)。还采用了验证性因素分析；使用McDonald'somega（ω）和Cronbach'salpha（α）评估可靠性。
26个项目中，共有23个项目的歧视水平很高(>1.7)，所有26名均落在建议的难度阈值内(-1.5至1.5).这些项目为其各自的因素/子域贡献了合理的信息水平。该措施还为3因素结构提供了一个勉强可接受的模型拟合(例如，比较拟合指数=0.88，塔克-刘易斯指数=0.87)和跨时间点的良好可靠性水平(ω和α>0.90)。
这里，我们使用IRT对FAQLQ-PF项目进行了新的重新分析。单个项目和分量表的纵向性能得到了证实，并确定了歧视程度最高的项目，表明该工具适用于FA治疗试验中的纵向测量。
对FAQLQ-PF的26个普遍回答的项目进行了分析，根据在第三阶段PEPITES研究期间进行的评估(基线，第12个月)，研究了EPIT对4-11岁花生过敏儿童的安全性和有效性。项目反应理论(IRT)用于评估FAQLQ-PF的心理测量参数(即，歧视,困难,和信息)。还采用了验证性因素分析；使用McDonald'somega（ω）和Cronbach'salpha（α）评估可靠性。
26个项目中，共有23个项目的歧视水平很高(>1.7)，所有26名均落在建议的难度阈值内(-1.5至1.5).这些项目为其各自的因素/子域贡献了合理的信息水平。该措施还为3因素结构提供了一个勉强可接受的模型拟合(例如，比较拟合指数=0.88，塔克-刘易斯指数=0.87)和跨时间点的良好可靠性水平(ω和α>0.90)。
这里，我们使用IRT对FAQLQ-PF项目进行了新的重新分析。单个项目和分量表的纵向性能得到了证实，并确定了歧视程度最高的项目，表明该工具适用于FA治疗试验中的纵向测量。
