## DDSolver, Mahalanobis distance and its 90% CI [Dissolution / BCS / IVIVC]

Dear yicaoting,

» If you want to use DDSolver to calculate Ma's distance, I can promise that I have compared the results of DDSolver with that of the famous paper which might be practically recommended by FDA. Moreover, I have compared DDSolver's Ma's distance with that of Mathematica, Mathematica is a famous numerical analysis software.
» Both comparisons are high satisfactor.

if I got it right (I can't see your code) you calculate the 90% CI of the MD simply as:
    MD + sqrt(Fval/K)
with K the scaling factor and Fval the critical F value from the Tsong et. al. paper.

Is this really that simple? How does this fit into the lagrange multiplier method mention in that paper?

How does this compare to the method of calculating CI's of MD elaborated in
Reiser, B. (2001)
"Confidence Intervals for the Mahalanobis Distance"
Communications in Statistics. Simulation and Computation, 30, 37-45
online resource

implemented in SAS (needs module IML) described here.

Regards,

Detlew