Department of Rehabilitation Medicine, University of Washington, Seattle, Washington, United States of America.
Hanger Institute for Clinical Research and Education, Austin, Texas, United States of America.
PLoS One. 2023 Nov 2;18(11):e0293848. doi: 10.1371/journal.pone.0293848. eCollection 2023.
Lower limb orthoses (LLOs) are externally-applied leg braces that are designed to improve or maintain mobility in people with a variety of health conditions that affect lower limb function. Clinicians and researchers are therefore often motivated to measure LLO users' mobility to select or assess the effectiveness of these devices. Patient-reported outcome measures (PROMs) can provide insights into important aspects of a LLO user's mobility for these purposes. However, few PROMs are available to measure mobility of LLO users. Those few that exist have issues that may limit their clinical or scientific utility. The objective of this study was to create a population-specific item bank for measuring mobility of LLO users. Previously-developed candidate items were administered in a cross-sectional study to a large national sample of LLO users. Responses from study participants (n = 1036) were calibrated to a graded response statistical model using Item Response Theory methods. A set of 39 items was found to be unidimensional, locally independent, and function without bias due to characteristics unrelated to mobility. The set of final calibrated items, termed the Orthotic Patient-Reported Outcomes-Mobility (OPRO-M) item bank, was evaluated for initial evidence of convergent, divergent, and known groups construct validity. OPRO-M was strongly correlated with existing PROMs designed to measure aspects of physical function. Conversely, OPRO-M was weakly correlated with PROMs that measured unrelated constructs, like sleep disturbance and depression. OPRO-M also showed an ability to differentiate groups with expected mobility differences. Two fixed-length short forms were created from the OPRO-M item bank. Items on the short forms were selected based on statistical and clinical criteria. Collectively, results from this study indicate that OPRO-M can effectively measure mobility of LLO users, and OPRO-M short forms can now be recommended for use in routine clinical practice and research studies.
下肢矫形器（LLO）是外部应用的腿部支具，旨在改善或维持各种影响下肢功能的健康状况的患者的活动能力。因此，临床医生和研究人员通常有动力测量 LLO 用户的活动能力，以选择或评估这些设备的有效性。患者报告的结果测量（PROM）可以为这些目的提供有关 LLO 用户活动能力的重要方面的见解。然而，用于测量 LLO 用户活动能力的 PROM 很少。现有的少数 PROM 可能存在限制其临床或科学实用性的问题。本研究的目的是创建一个用于测量 LLO 用户活动能力的特定于人群的项目库。先前开发的候选项目在一项横断面研究中在 LLO 用户的大型全国样本中进行了管理。研究参与者（n = 1036）的反应使用项目反应理论方法根据分级响应统计模型进行了校准。发现一组 39 个项目具有单维性、局部独立性，并且由于与活动能力无关的特征而没有功能偏差。一组最终校准的项目，称为矫形器患者报告的结果-活动能力（OPRO-M）项目库，用于评估初始收敛性、发散性和已知群体结构有效性的证据。OPRO-M 与旨在测量身体功能各个方面的现有 PROM 高度相关。相反，OPRO-M 与测量不相关结构（如睡眠障碍和抑郁）的 PROM 相关性较弱。OPRO-M 还显示出区分具有预期活动能力差异的群体的能力。从 OPRO-M 项目库中创建了两个固定长度的简短表格。简短表格上的项目是根据统计和临床标准选择的。总的来说，这项研究的结果表明，OPRO-M 可以有效地测量 LLO 用户的活动能力，现在可以推荐 OPRO-M 简短表格用于常规临床实践和研究研究。
