Tao Wei, Haley Stephen M, Coster Wendy J, Ni Pengsheng, Jette Alan M
Health and Disability Research Institute, School of Public Health, Boston University Medical Center, Boston, MA 02118-2639, USA.
Arch Phys Med Rehabil. 2008 Jun;89(6):1046-53. doi: 10.1016/j.apmr.2007.11.036.
To develop and explore the feasibility of a functional staging system (defined as the process of assigning subjects, according to predetermined standards, into a set of hierarchic levels with regard to their functioning performance in mobility, daily activities, and cognitive skills) based on item response theory (IRT) methods using short forms of the Activity Measure for Post-Acute Care (AM-PAC) and to compare the criterion validity and sensitivity of the IRT-based staging system to a non-IRT-based staging system developed for the FIM instrument.
Prospective, longitudinal cohort study of patients interviewed at hospital discharge and 1, 6, and 12 months after inpatient rehabilitation.
Follow-up interviews conducted in patients' homes.
Convenience sample of 516 patients (47% men; sample mean age, 68.3y) at baseline (retention at the final follow-up, 65%) with neurologic, lower-extremity orthopedic, or complex medical conditions.
Not applicable.
AM-PAC basic mobility, daily activity, and applied cognitive activity stages; FIM executive control, mobility, activities of daily living, and sphincter stages. Stages refer to the hierarchic levels assigned to patients' functioning performances.
We were able to define IRT-based staging definitions and create meaningful cut scores based on the 3 AM-PAC short forms. The IRT stages correlated as well or better to the criterion items than the FIM stages. Both the IRT-based stages and the FIM stages were sensitive to changes throughout the 6-month follow-up period. The FIM stages were more sensitive in detecting changes between baseline and 1-month follow-up visits. The AM-PAC stages were more discriminant in the follow-up visits.
An IRT-based staging approach appeared feasible and effective in classifying patients throughout long-term follow-up. Although these stages were developed from short forms, this staging methodology could also be applied to improve the meaning of scores generated from IRT-based computerized adaptive testing in future work.
基于项目反应理论（IRT）方法，利用急性后期护理活动量表（AM-PAC）简表开发并探索一种功能分期系统（定义为根据预定标准，将受试者在移动性、日常活动和认知技能方面的功能表现划分为一组层次水平的过程）的可行性，并将基于IRT的分期系统与为FIM工具开发的非IRT分期系统的标准效度和敏感性进行比较。
对出院时以及住院康复后1个月、6个月和12个月接受访谈的患者进行前瞻性纵向队列研究。
在患者家中进行随访访谈。
516例患者的便利样本（47%为男性；样本平均年龄68.3岁），基线时患有神经疾病、下肢骨科疾病或复杂内科疾病（最终随访时的保留率为65%）。
不适用。
AM-PAC基本移动性、日常活动和应用认知活动阶段；FIM执行控制、移动性、日常生活活动和括约肌阶段。阶段是指分配给患者功能表现的层次水平。
我们能够基于3个AM-PAC简表定义基于IRT的分期定义并创建有意义的划界分数。IRT阶段与标准项目的相关性与FIM阶段相当或更好。基于IRT的阶段和FIM阶段在整个6个月的随访期内对变化均敏感。FIM阶段在检测基线和1个月随访之间的变化时更敏感。AM-PAC阶段在随访中更具区分性。
基于IRT的分期方法在长期随访中对患者进行分类似乎是可行且有效的。尽管这些阶段是从简表中开发出来的，但这种分期方法也可应用于未来工作中，以改善基于IRT的计算机自适应测试所产生分数的意义。
