Identifying a total of 28 joints in the development and validation of Modified Disease Activity Scores (DAS)

The canonical discriminant analyses were used to develop DAS scores and were used for establishing correlational and criterion validity. The disease duration influence on the development of DAS was also investigated in this process. 

There was not any influence on the duration of disease found during the process. The 28 joint counts included in Modified DAS discriminated between low and high activity based on the clinical investigations of rheumatologists. 

Just like the validation of disease activity scores that reflect comprehensive joint counts, the Modified DAS is equally valid.

Reference Link:onlinelibrary.wiley.com/doi/10.1002/art.1780380107