Improving the Action Research Arm test: a unidimensional hierarchical scale

• DOI: 10.1191/0269215502cr534oa
• Publication Date: 2003-01-07T02:07:02Z
• Authors: Johanna H van der...; Leo D Roorda; Heleen Beckerman; Gustaaf J Lankhorst; Lex M Bouter
• Keywords: Sample (material)

Background: The Action Research Arm (ARA) test is a performance of upper extremity motor function which consists 19 items divided into four hierarchical subtests. This multidimensionality has not yet been tested empirically. Objective: To investigate the dimensionality ARA test. Design: Cross-sectional study involving sample 63 chronic stroke patients. Methods: A Mokken scale analysis was performed. Results: revealed one strong unidimensional containing all items, scalability coefficient H 0.79, while per item ranged from 0.69 to 0.86. reliability rho equalled 0.98, indicating very high internal consistency. subset 15 out showed an invariant item-ordering. Conclusion: scale. use subtests, as proposed in original description instrument, supported by present findings. 15-item presented here can be used for adaptive testing, i.e. using only selected based on prior knowledge about patient's abilities, thus minimizing testing time.