TY - JOUR
T1 - Improving the action research arm test
T2 - A unidimensional hierarchical scale
AU - van der Lee, Johanna H.
AU - Roorda, Leo D.
AU - Beckerman, Heleen
AU - Lankhorst, Gustaaf J.
AU - Bouter, Lex M.
PY - 2002/9/1
Y1 - 2002/9/1
N2 - Background: The Action Research Arm (ARA) test is a performance test of upper extremity motor function which consists of 19 items divided into four hierarchical subtests. This multidimensionality has not yet been tested empirically. Objective: To investigate the dimensionality of the ABA test. Design: Cross-sectional study involving a sample of 63 chronic stroke patients. Methods: A Mokken scale analysis was performed. Results: The Mokken scale analysis revealed one strong unidimensional scale containing all 19 items, of which the scalability coefficient H was 0.79, while H per item ranged from 0.69 to 0.86. The reliability coefficient rho equalled 0.98, indicating a very high internal consistency. A subset of 15 out of 19 items showed an invariant hierarchical item-ordering. Conclusion: The ABA test is a unidimensional scale. The use of subtests, as proposed in the original description of the instrument, is not supported by the present findings. The 15-item scale presented here can be used for adaptive testing, i.e. using only a selected subset of items based on prior knowledge about the patient's abilities, thus minimizing testing time.
AB - Background: The Action Research Arm (ARA) test is a performance test of upper extremity motor function which consists of 19 items divided into four hierarchical subtests. This multidimensionality has not yet been tested empirically. Objective: To investigate the dimensionality of the ABA test. Design: Cross-sectional study involving a sample of 63 chronic stroke patients. Methods: A Mokken scale analysis was performed. Results: The Mokken scale analysis revealed one strong unidimensional scale containing all 19 items, of which the scalability coefficient H was 0.79, while H per item ranged from 0.69 to 0.86. The reliability coefficient rho equalled 0.98, indicating a very high internal consistency. A subset of 15 out of 19 items showed an invariant hierarchical item-ordering. Conclusion: The ABA test is a unidimensional scale. The use of subtests, as proposed in the original description of the instrument, is not supported by the present findings. The 15-item scale presented here can be used for adaptive testing, i.e. using only a selected subset of items based on prior knowledge about the patient's abilities, thus minimizing testing time.
UR - http://www.scopus.com/inward/record.url?scp=0036745462&partnerID=8YFLogxK
U2 - 10.1191/0269215502cr534oa
DO - 10.1191/0269215502cr534oa
M3 - Article
C2 - 12392340
AN - SCOPUS:0036745462
VL - 16
SP - 646
EP - 653
JO - Clinical Rehabilitation
JF - Clinical Rehabilitation
SN - 0269-2155
IS - 6
ER -