Objective

To confirm the structural validity of the Trunk Assessment Scale for Spinal Cord Injury (TASS).

Participants and Methods

We evaluated 104 Japanese individuals with a spinal cord injury (SCI) (age 63.5 ± 12.2 years; 64 with tetraplegia) with the TASS 1−3 times. We conducted a Rasch analysis to assess the TASS’ unidimensionality, fit statistics, category probability curve, ceiling/floor effects, local independence, reliability, and difference item function (DIF).

Results

The TASS was observed to be a unidimensional and highly reproducible scale of item difficulty hierarchy that sufficiently identifies the superiority of the examinee's ability. The TASS was easy for the participants of this study. One TASS item was a misfit based on the infit and outfit mean square; another item also showed a DIF contrast for age. Several items were found to require a synthesis or modification of the content. The TASS showed a floor effect, and most of the non-scorers were individuals with a complete SCI.

Conclusion

Our findings clarify the structural validity of the TASS, and our analyses revealed that the TASS includes an unfitness item and was less challenging for individuals with SCIs. The improvements suggested by these results provide important information for modifying the TASS to a more useful instrument.

中文翻译：

---

脊髓损伤躯干评估量表 (TASS) 的结构有效性与 Rasch 分析对脊髓疾病患者的影响

客观的

确认脊髓损伤躯干评估量表 (TASS) 的结构有效性。

参与者和方法

我们使用 TASS 对 104 名患有脊髓损伤 (SCI) 的日本人（年龄 63.5 ± 12.2 岁；64 名四肢瘫痪）进行了 1−3 次评估。我们进行了 Rasch 分析来评估 TASS 的一维性、拟合统计量、类别概率曲线、上限/下限效应、局部独立性、可靠性和差异项函数 (DIF)。

结果

据观察，TASS 是一维且高度可重复的项目难度等级量表，足以识别考生能力的优越性。TASS 对于本研究的参与者来说很容易。根据穿着和服装的均方，TASS 的一件商品是不合身的；另一项也显示了年龄的 DIF 对比。发现有几个项目需要对内容进行综合或修改。TASS 显示了下限效应，大多数未评分者都是具有完整 SCI 的个体。

结论

我们的研究结果阐明了 TASS 的结构有效性，并且我们的分析表明 TASS 包含一个不健康项目，并且对于 SCI 个体来说挑战性较小。这些结果所建议的改进为将 TASS 修改为更有用的工具提供了重要信息。