modifiers

Is there a certain age, when receiving immunizations, that the modifier on an office visit changes? For example, when billing for an office visit & receiving shots the dr. uses a modifier 59. The insurance companies have denied it so we corrected it to a 25. After looking back, I see where some insurance companies paid the visit, along with shots, using the modifier 59. Can anyone shed some light on this topic?

re: modifiers

With an e/m you always use the modifier 25. If you were doing two different procedures then you would use the 59. Age is not a factor. Not sure about the other insurances paying with the 59 modifier, unless there were 2 procedures and it was attached to one of the procedures.
http://www.poweryourpractice.com/revenue-cycle-management/modifier-59-25-91-guide-coders/
This should help explain these modifiers more clearly for you.