Blackburn, M., van Vliet, P., et al. (2002). "Reliability of measurements obtained with the modified Ashworth scale in the lower extremities of people with stroke." Physical Therapy 82(1): 25.
Bohannon, R. and Smith, M. (1987). "Interrater reliability of a modified Ashworth scale of muscle spasticity." Physical Therapy 67(2): 206.
Brashear, A., Zafonte, R., et al. (2002). "Inter-and intrarater reliability of the Ashworth Scale and the Disability Assessment Scale in patients with upper-limb poststroke spasticity* 1." Archives of physical medicine and rehabilitation 83(10): 1349-1354.
Gregson, J., Leathley, M., et al. (1999). "Reliability of the Tone Assessment Scale and the modified Ashworth scale as clinical tools for assessing poststroke spasticity." Archives of physical medicine and rehabilitation 80(9): 1013-1016. Find it on PubMed
Gregson, J., Leathley, M., et al. (2000). "Reliability of measurement of muscle tone and muscle power in stroke patients." Age and Ageing 29(3): 223.
Haas, B., Bergström, E., et al. (1996). "The inter rater reliability of the original and of the modified Ashworth scale for the assessment of spasticity in patients with spinal cord injury." Spinal Cord 34(9): 560-564.
Primary use / Purpose:
In the original Ashworth Scale, resistance to passive movement about a joint with varying degrees of velocity is measured on a scale of 0 (no resistance) to 4 (rigidity). In the modified Ashworth Scale, a 1+ scoring category is added to indicate resistance through less than half of the movement (Bohannon & Smith, 1987).
Psychometric evaluation of the MAS is discussed in Blackburn et al. (2002) and Gregson et al. (1999; 2000).