Objectives: The main purpose of this research was to study and contribute to an accurate test of spastic limb. The intra, inter rater reliability of the test was examined.

Methods: The present study was carried out in two parts In the first part of the study, the modified Ashworth Scale with Intermediate Scores (ASIS) was studied. During the second part of the study the intra, inter rater reliability of the ASIS were evaluated. Twenty cerebral palsy individuals who had spasticity on their knee flexors, eleven males and nine females, recruited in the study, their mean age was 25.4 (range from 18 to 35 years of age). The limbs were tested according to the ASIS. The same subjects were measured twice during a week period by each tester.

Results: According to the first part of the study intermediate scores were added to the modified Ashworth scale. In the second part of the study inter operators and intra operators’ reliability of the ASIS were analyzed. Pearson's correlations coefficient were 0.78 and 0.89 for intra rater reliability and 0.46 and 0.53 for inter rater reliability.

Discussion: It appears that the Modified Ashworth Scale would be more sensitive if an intermediate score was added to each score (2-4). It was concluded that the intra rater reliability of ASIS measurements was high and the inter rater reliability of ASIS measurements was low.