[R] qcc package & syndromic surveillance (multivar CUSUM?)

[adiamond@fas.harvard.edu]

Dear R Community:

I am working on a public health early warning system, and 
I see that the qcc package allows for CUSUM and other statistical quality tests
but I am not sure if my project is a good match for qcc functions as written.
Any advice you may have is very much appreciated.

I have four years worth of daily counts of emergency room admissions for 
different conditions (e.g. respiratory, neurologic, etc) from several local 
hospitals.  the data looks like this...

DAY 1
              Respiratory     Neuro   ...
Hospital A:       10		12
.                  .             .
.                  .             .
Hospital F:        7            14


DAY 2         Respiratory     Neuro   ...
Hospital A:       10		12
.                  .             .
.                  .             .
Hospital F:        7            14    ...

etc.,

and my goal is to do a kind of multivariate quality control test (without 
fitting a GLM), that would run each day after the data is updated and be able 
to answer the question: 
"Has there been a significant variation in the central tendency of the data?"

An analogous problem would be detecting the early signs of a shift in global 
trading patterns by examining stock market indexes in different countries 
around the world, updating and testing the data each business day. 

Thank you, 

Alexis Diamond