- 作者：Asaduzzaman Khan ; a.khan2@uq.edu.au ; Chi-Wen Chien ; Sandra G. Brauer
- 关键词：Item response theory ; Rasch analysis ; UL-MAS ; Relative precision ; Summative scoring ; Patients with stroke
- 刊名：Journal of Clinical Epidemiology
- 出版年：2013
- 出版时间：June, 2013
- 年：2013
- 卷：66
- 期：6
- 页码：681-687
- 全文大小：123 K
Objective
To compare the discriminatory ability of Rasch-based and summative scoring in the context of assessing upper limb function of patients with stroke.Study Design and Setting
Data were from a cohort study of 497 adults with stroke undergoing physiotherapy. Upper limb function was assessed at admission and discharge using the upper limb subscale of the Motor Assessment Scale (UL-MAS). Rasch analysis was used to transform raw UL-MAS scores into interval measures. A relative precision (RP) index was used to differentiate patients by discharge destination.
Results
The analysis confirmed the unidimensional structure of UL-MAS at both admission and discharge and demonstrated the adequate fit of the items. The RP index favored the Rasch-based scoring over the summative scoring in differentiating between the two patient groups, with significant gains in precision at admission (15 % ) and discharge (11 % ). When examining patients in the upper or lower quartile of UL-MAS, the gains in precision were statistically significant in favor of the Rasch-based scoring, with 20 % precision at admission and 19 % precision at discharge.
Conclusion
Rasch-based scoring was more precise in differentiating patient groups by discharge destination than the summative scoring used to measure upper limb function, especially at the extreme range of the scale.