We have collected pre and post cognitive function data using the ADAS-COG, but are struggling to find in-depth guidelines for analysis of data.
For example, how is the number cancellation section scored? Surely it needs to be transferred in to some kind of scaled score, as this item is positively scored and the rest negatively. Do all subscales need transforming to a scaled score so that, for example, word recall (scored out of 10) does not contribute more overall than naming (scored out of 5)?
Dear Natasha ,
the ADAS-Cog is usually analyzed by deriving a ADAS-Cog total score. The scoring of number cancellation is - to my knowledge - described in Mohs et al. 1997 (Alzheimers Disease and Associated Disorder Vol. 11 p.13-21).
However note that depending on what your patient collective under study is (AD dementia or MCI patients, healthy elderly?), some ADAS-Cog subscales will show ceiling effects and no sensitivity to change. There is an evolving body of literature on how to deal with this. Just do a literature research with search terms like "ADAS-Cog", sensitivity, responsivity, change. You will find lots of information then, also on how to derive the ADAS Cog Total Score ( I wonder why this is not explained in your manual).
I hope this helped.
Good Luck
Steffen
Thank you very much for you help Steffen. The instructions for number cancellation in the Mohs et al paper still seem to leave you with a positive score, while all others are negative, so I'm just wondering how it gets incorporated in to the total score, if at all. I will investigate further!
Dear Natasha,
you might find answers in the ADNI protocols maybe:
http://www.adni-info.org/Scientists/CognitiveTesting.aspx
Dear Natasha,
Have you ever thought of performing a linear regression to find out how much each of the tasks load on the total score? It would be interesting to get those data and provide a simple algorithm for other researchers. Best.
- Badges
- Science topic
- Similar topics
- Geoscience
- Asia
- India