A critical evaluation of the Incapacity Status Scale.

The Incapacity State Scale (ISS) of the research version of the Minimal Record of Disability in Multiple Sclerosis has been tested in parallel with Assessment of the Activities of Daily Living (ADL) Index. Reliance of the ISS scoring on the use of aids and adaptive devices was found to be a major source of variation. It is suggested that the general scoring of the proposed ISS scale should be modified so that it employs that of the ADL method, i.e. measuring only independence (irrespective of the use of side and adaptive devices), partial and total dependence.