I would like to echo Alan's issue. The testing script is very helpful and in the two trusts I have been involved with have found the script extremely useful. It took a great deal of time booking in historical results, then waiting for the rules to kick in, then booking in the next. When I tried booking in the results it haste the calculator did not perform as expected. 
I am fortunate in that in my host trust, there will be time (and we have plenty of consultant renal support) to run this suppressed along-side our current in-house system. It would be interesting to find out the implementation strategy of other laboratories.  

On another note I thought I would share my experience with the testing so far. 
In summary :-
1. CSC algorithm testing in adults according to the script performs as expected.
2. Paediatric patients testing is difficult as the script has to reflect your reference range used.
3. If CSC explained exactly how it was performing the calculation it would make testing much easier.
4. It would really help in future if the calculated creatinine baseline was available in the program so you could check. Do we feel this should also be reported? My personal answer would be yes.

John