searching a string for a number

I am trying to validate test codes and making sure they dont have numbers in them. i have tried the following commands with no luck:

{[string is digit -strict $testCode]}

and

if {![regexp -all {[^0-9]} $testCode]} {

set errormsg “WARN: ORM Killed – Numeric test code: $patientAcct,

$parent/$placerid/$fillerid, $dept/$testCode/$priority,$ordertype/$orderStatus”

set actionFlag “KILL”

}

They only work if the whole test code is a number, i was hoping that it would work if only at least one character is a number. So i guess in a sense it is working but what do i have to add to search for any number?

Thanks.