The [ask tag has the following options:
If the user is unsure of what User I.D.'s are they can enter a '?' (or a '/') and a box will appear listing all the users in alphabetical order and they can scoll up/down as needed.
With the USER option, you may want to restrict the list; If you only want, for example, Veterinary Surgeons, Nurses and locums to appear this can be done with a PARAMS.txt entry.
Look at the user groups you have added the users too make a note of the groups you DO NOT want to appear, add the entry:
Filter_User_Group = x y zWhere x y z are the groups to ignore - these groups will be filtered out. Retired users will automatically be removed.
While the list is sorted into user order, you may want to refine this by having sub-groups, all Vets, then all locums and finally all nurses. User the params.txt entry:
User_Group_Order = a b c
In this case all members of group 'a' will be first, then group 'b' and group 'c' this will be followed by all other user.