Abstract：
BACKGROUND: Psychosocial evaluations are mandatory for transplant listing, however the methodology for creating psychosocial risk stratifications is unclear. The Standford Psychosocial Integrated Psychosocial Assessment for Transplant Scale is the most commonly used instrument, however its interitem validity has never been examined.
OBJECTIVE: To investigate the interitem validity of a psychosocial assessment tool for transplant candidates among a sample of thoracic transplant candidates.
METHODS: Clinic data consisting of Stanford Integrated Psychosocial Assessment for Transplant administrations from 173 heart and lung transplant candidates were fit to a partial credit model. Data were subsequently fit to 4 separate partial credit models based on subscale categories, demonstrating the discrimination parameter estimate of each item. Differential item functioning analyses were conducted on the data within each subscale by sex to investigate potential bias produced by each item.
RESULTS: The initial partial credit model using the full scale did not converge, indicating the subscales possibly did not measure the same underlying construct. Subscale discrimination parameter estimates demonstrated that most items were adequately or highly discriminative. The item measuring history of substance use demonstrated poor fit and differential item functioning.
CONCLUSIONS: While the Stanford Integrated Psychosocial Assessment for Transplant has demonstrated strong potential as a standardized framework for psychosocial assessments in transplant, this study identified some areas for improvement in the scoring system. The subscale scores appeared to show greater construct validity when utilized individually than when aggregated to form a total score. The substance use/abuse/dependence item did not fit well into its respective subscale. Future studies should aim to optimize the scoring system and re-asses its construct validity to improve its accuracy in discriminating between high-risk candidates and those needing psychosocial assistance.
OBJECTIVE: To investigate the interitem validity of a psychosocial assessment tool for transplant candidates among a sample of thoracic transplant candidates.
METHODS: Clinic data consisting of Stanford Integrated Psychosocial Assessment for Transplant administrations from 173 heart and lung transplant candidates were fit to a partial credit model. Data were subsequently fit to 4 separate partial credit models based on subscale categories, demonstrating the discrimination parameter estimate of each item. Differential item functioning analyses were conducted on the data within each subscale by sex to investigate potential bias produced by each item.
RESULTS: The initial partial credit model using the full scale did not converge, indicating the subscales possibly did not measure the same underlying construct. Subscale discrimination parameter estimates demonstrated that most items were adequately or highly discriminative. The item measuring history of substance use demonstrated poor fit and differential item functioning.
CONCLUSIONS: While the Stanford Integrated Psychosocial Assessment for Transplant has demonstrated strong potential as a standardized framework for psychosocial assessments in transplant, this study identified some areas for improvement in the scoring system. The subscale scores appeared to show greater construct validity when utilized individually than when aggregated to form a total score. The substance use/abuse/dependence item did not fit well into its respective subscale. Future studies should aim to optimize the scoring system and re-asses its construct validity to improve its accuracy in discriminating between high-risk candidates and those needing psychosocial assistance.
摘要：
目的：在胸部移植候选人样本中，调查移植候选人的心理社会评估工具的项目间有效性。
方法：由来自173个心脏和肺移植候选人的斯坦福移植心理社会综合评估（SIPAT）给药组成的临床数据符合部分信用模型（PCM）。随后根据子量表类别将数据拟合到四个单独的PCM，演示每个项目的判别参数估计。按性别对每个子量表内的数据进行差异项目功能分析，以调查每个项目产生的潜在偏倚。
结果：使用满刻度的初始PCM未收敛，表明子量表可能没有测量相同的基础结构。子量表判别参数估计表明，大多数项目具有充分或高度的判别性。测量物质使用历史的项目显示出不良的配合和差异项目功能。
结论：虽然SIPAT已显示出作为移植中社会心理评估的标准化框架的强大潜力，这项研究确定了评分系统需要改进的一些地方.单独使用时，子量表得分似乎显示出比汇总形成总分时更高的构造效度。药物使用/滥用/依赖项目不适合其各自的子量表。未来的研究应旨在优化评分系统并重新评估其结构效度，以提高区分高风险候选人和需要心理社会援助的候选人的准确性。
方法：由来自173个心脏和肺移植候选人的斯坦福移植心理社会综合评估（SIPAT）给药组成的临床数据符合部分信用模型（PCM）。随后根据子量表类别将数据拟合到四个单独的PCM，演示每个项目的判别参数估计。按性别对每个子量表内的数据进行差异项目功能分析，以调查每个项目产生的潜在偏倚。
结果：使用满刻度的初始PCM未收敛，表明子量表可能没有测量相同的基础结构。子量表判别参数估计表明，大多数项目具有充分或高度的判别性。测量物质使用历史的项目显示出不良的配合和差异项目功能。
结论：虽然SIPAT已显示出作为移植中社会心理评估的标准化框架的强大潜力，这项研究确定了评分系统需要改进的一些地方.单独使用时，子量表得分似乎显示出比汇总形成总分时更高的构造效度。药物使用/滥用/依赖项目不适合其各自的子量表。未来的研究应旨在优化评分系统并重新评估其结构效度，以提高区分高风险候选人和需要心理社会援助的候选人的准确性。
