Objective: To assess the internal construct validity (ICV) of the five Brain Injury Rehabilitation Trust Personality Questionnaires (BIRT-PQ) with Classical Test Theory methods.Methods: Multicenter cross-sectional study involving 11 Italian rehabilitation centers. BIRT-PQs were administered to patients with severe Acquired Brain Injury and their respective caregivers. ICV was assessed by the mean of an internal consistency analysis (ICA) and a Confirmatory Factor Analysis (CFA).Results: Data from 154 patients and their respective caregivers were pooled, giving a total sample of 308 subjects. Despite good overall values (alphas ranging from 0.811 to 0.937), the ICA revealed that several items within each scale did not contribute as expected to the total score. This result was confirmed by the CFA, which showed the misfit of the data to a unidimensional model (RMSEA ranging from 0.077 to 0.097). However, after accounting for local dependency found within the data, fitness to a unidimensional model improved significantly (RMSEA ranging from 0.050 to 0.062).Conclusion: Despite some limitations, our analyses demonstrated the lack of ICV for the BIRT-PQ total scores. It is envisaged that a more comprehensive ICV analysis will be performed with Rasch analysis, aiming to improve both the measurement properties and the administrative burden of each BIRT-PQ.

中文翻译：

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五个脑损伤康复信托人格问卷（BIRT-PQ）的单维性可能得到改善：来自经典心理计量学的初步证据。

目的：使用经典测试理论方法评估五个脑损伤康复信任人格问卷（BIRT-PQ）的内部结构效度（ICV）。方法：涉及11个意大利康复中心的多中心横断面研究。将BIRT-PQ给予患有严重后天性脑损伤的患者及其各自的护理人员。通过内部一致性分析（ICA）和验证性因子分析（CFA）的平均值对ICV进行评估。结果：收集了154例患者及其各自护理人员的数据，总共抽取了308名受试者的样本。尽管总体值不错（alpha值从0.811到0.937），但ICA显示，每个量表中的多个项目对总分的贡献均未达到预期。终审法院确认了这一结果，这表明数据与一维模型不匹配（RMSEA范围为0.077至0.097）。然而，在考虑了数据中的局部依赖性之后，对一维模型的适应性显着提高（RMSEA在0.050到0.062之间）。结论：尽管有一些限制，我们的分析表明BIRT-PQ总分缺乏ICV。预计将使用Rasch分析进行更全面的ICV分析，旨在同时改善每个BIRT-PQ的测量属性和管理负担。我们的分析表明，BIRT-PQ总分缺乏ICV。预计将使用Rasch分析进行更全面的ICV分析，旨在同时改善每个BIRT-PQ的测量属性和管理负担。我们的分析表明，BIRT-PQ总分缺乏ICV。预计将使用Rasch分析进行更全面的ICV分析，旨在同时改善每个BIRT-PQ的测量属性和管理负担。