[Jpn J Rehabil Med 2002; 39: 409-415; Original]

A Study of Inter-rater Reliability of the Modified Ashworth Scale(MAS) in Spasticity in Patients with Stroke

Tetsuya TSUJI, Tetsuo OTA, Akio KIMURA, Naoichi CHINO, Shigenobu ISHIGAMI

Department of Rehabilitation Medicine, Shizuoka Cancer Hospital and Reseach Institute

(Received 26 April 2002; accepted 14 June 2002)

Abstract: Objectives: To establish reliability of the modified Ashworth scale for measuring muscle tone in a range of muscle groups (elbow extensors, wrist extensors, knee flexors and ankle dorsiflexors) in subacute and chronic stroke patients. Design: A cross-sectional study involving randomized measurements by two raters. We estimated reliability using the χ statistic with quadratic weighs (χw). Setting: A stroke rehabilitation unit. Subjects: People admitted to hospital with a subacute or chronic stroke (median age, 68 yrs, 16 men and 8 women). Results: Inter-rater agreement for the modified Ashworth scale was fair to excellent for all tested muscle groups (χw=0.66-0.76) and excellent for the total score (χw=0.91). Conclusions: The modified Ashworth scale was reliable in all tested muscle groups. The total score also demonstrated reliability. The rater's manual to examine the modified Ashworth scale was useful for improvement of reliability.

Key words: cerebrovascular disorder, hemiparesis, modified Ashworth scale (MAS), inter-rater reliability, spasticity