Bohannon and Smith introduced the Modified Ashworth Scale (MAS) by adding a '1+' grade to the original 5-point Ashworth scale. The study tested whether two experienced, pre-calibrated raters could reliably grade elbow flexor spasticity in 30 patients with CNS lesions. It directly answers the question: is this bedside spasticity test reliable enough to use as an outcome measure?
When you assess spasticity at the bedside, the MAS is the scale you use — and this paper is why it exists.
The original Ashworth scale had no published reliability data and its grade '1' was too coarse for the hemiplegia population, where most patients clustered at the low end. Bohannon and Smith fixed this by adding grade '1+' and then actually tested whether the modified scale was reliable, producing the foundational reliability data the field lacked.
In practice: use the MAS to document spasticity before and after interventions (baclofen, botulinum toxin, electrical stimulation), but be aware that reliability is best established in upper limb testing between calibrated raters. For lower extremity assessment (post-stroke, spinal cord injury, cerebral palsy), reliability is lower. Particularly at the 1/1+ boundary this paper introduced.
The recurring tension in spasticity research traces back to this paper: the 1/1+ distinction that made the scale more sensitive is also the source of its greatest interrater disagreement.
Bohannon and Smith introduced the Modified Ashworth Scale (MAS) by adding a '1+' grade to the original 5-point Ashworth scale. The study tested whether two experienced, pre-calibrated raters could reliably grade elbow flexor spasticity in 30 patients with CNS lesions. It directly answers the question: is this bedside spasticity test reliable enough to use as an outcome measure?
When you assess spasticity at the bedside, the MAS is the scale you use — and this paper is why it exists.
The original Ashworth scale had no published reliability data and its grade '1' was too coarse for the hemiplegia population, where most patients clustered at the low end. Bohannon and Smith fixed this by adding grade '1+' and then actually tested whether the modified scale was reliable, producing the foundational reliability data the field lacked.
In practice: use the MAS to document spasticity before and after interventions (baclofen, botulinum toxin, electrical stimulation), but be aware that reliability is best established in upper limb testing between calibrated raters. For lower extremity assessment (post-stroke, spinal cord injury, cerebral palsy), reliability is lower. Particularly at the 1/1+ boundary this paper introduced.
The recurring tension in spasticity research traces back to this paper: the 1/1+ distinction that made the scale more sensitive is also the source of its greatest interrater disagreement.