Franchignoni Franco, Giordano Andrea, Ferriero Giorgio, Muñoz Susana, Orlandini Duccio, Amoresano Amedeo
Unit of Occupational Rehabilitation and Ergonomics, Salvatore Maugeri Foundation, Clinica del Lavoro e della Riabilitazione, IRCCS, Veruno, NO, Italy.
Prosthet Orthot Int. 2007 Dec;31(4):394-404. doi: 10.1080/03093640701253952.
The aim of this study was to perform a Rasch analysis on the 5-level ordinal scale version of the Locomotor Capabilities Index (LCI-5), in order to investigate rating scale quality and conduct reliability and validity assessments. A questionnaire was mailed to 144 subjects who had undergone lower limb amputation (LLA) in the previous five years and completed a rehabilitation and prosthetic training programme. A total of 123 persons (85%) responded to the questionnaire, a self-report assessment of prosthetic capability and performance which included the LCI-5, the Mobility Section of the Prosthesis Evaluation Questionnaire (PEQ-MS) and other variables associated to prosthetic wear and use. Following Rasch analysis and expert review, the LCI-5 response categories level 1 ('yes, if someone helps me') and 2 ('yes, if someone is near me') were combined into a single category and 4 items were deleted (due to misfitting). The remaining 10 items fitted the Rasch model (LCI10-4) and demonstrated good reliability (person separation reliability = 0.94, item separation reliability = 0.98) and internal construct validity. Moreover, the good correlation with the PEQ-MS (r(s) = 0.77) and with prosthetic wear and use (r(s) range 0.34 - 0.51) supported the convergent validity of the scale. In conclusion, Rasch analysis provided the rationale for improving the measurement qualities of the LCI-5, refining its rating scale (through category diagnostics), identifying those items most useful for measuring the intended construct (as per the indexes of unidimensionality and internal construct validity) and showing that one can place high confidence in the consistency of both the person-ability and item-difficulty estimates obtained (reliability).
本研究旨在对运动能力指数的5级有序量表版本（LCI - 5）进行拉施分析，以调查量表质量并进行信效度评估。向144名在过去五年内接受过下肢截肢（LLA）并完成康复和假肢训练计划的受试者邮寄了一份问卷。共有123人（85%）回复了问卷，这是一份关于假肢能力和表现的自我报告评估，包括LCI - 5、假肢评估问卷的活动部分（PEQ - MS）以及与假肢穿戴和使用相关的其他变量。经过拉施分析和专家评审，LCI - 5的反应类别1级（“是的，如果有人帮助我”）和2级（“是的，如果有人在我附近”）被合并为一个类别，4个项目被删除（由于拟合不佳）。其余10个项目符合拉施模型（LCI10 - 4），并表现出良好的信度（人员分离信度 = 0.94，项目分离信度 = 0.98）和内部结构效度。此外，与PEQ - MS的良好相关性（r(s) = 0.77）以及与假肢穿戴和使用的相关性（r(s)范围为0.34 - 0.51）支持了该量表的收敛效度。总之，拉施分析为改善LCI - 5的测量质量、完善其评定量表（通过类别诊断）、识别对测量预期结构最有用的项目（根据单维度性和内部结构效度指标）提供了理论依据，并表明人们可以对所获得的人员能力和项目难度估计的一致性（信度）充满高度信心。
