What is the major limitation when using existing clinical records?

to provide benchmarks

nope, but i have cleaned my brush in my cup of not as potentially harmful but nevertheless, very upsetting for scottish/british folks. especially if you've used the last teabag for it

explanation:

there could be something in that . . i am indeed an old scottish man!

there's a bit of bolshie-ness with it too though. i won't let go of the old ways . . tea and whisky . . whether the young whippersnappers like it or not!