I have confidencial alpha and numeric information on Excel spreadsheets
(columns) that I would like to convert (code crosswalk) to useless
information to others. I would like to be able to convert the data back if I
need to use it. The information is typically patient names and account
numbers that must be kept secure. Usually I strip off the patient
information and retain the other columns, but sometimes I need to audit to
source data to follow-up on issues. Any recommendations how I can do this
to different spreadsheets?

Thanks in advance for any thoughts on this! -Bill