Optimizing ADAS-Cog Worksheets: A Survey of Clinical Trial Rater s’ Perceptions

The Alzheimer's Disease Assessment Scale-Cognitive subscale (ADASCog) remains the most widely used test of longitudinal cognitive functioning in Alzheimer's disease (AD) clinical trials. Unlike most neuropsychological tests, the ADAS-Cog source documentation worksheets are not uniform across clinical trials, and vary by document layout, inclusion of administration and/or scoring instructions, and documentation of subtest scoring (e.g., recording correct versus incorrect scores), among other differences. Many ADAS-Cog test administrators (raters) participate in multiple AD trials and switching between different ADAS-Cog worksheets may increase the likelihood of administration and/or scoring mistakes that lessen the reliability of the instrument. An anonymous online survey sought raters' experiences with ADAS-Cog worksheets and their opinions on the design and content of the worksheets.Results of the survey indicated preference for structure and standardization of the ADASCog worksheets, which has been considered in the development of a standard ADAS-Cog source document by the Alzheimer's Disease Cooperative Study (ADCS) Working Group.