I am getting mixed reviews on the time required for mod sed in order to bill 99144 (first 30 mins). per CPT, for time based codes, greater than 50% is required which in this case it would be 16 mins of mod sed needed to bill, however, I've been advised by some that this rule does not apply with "first" and "up to" codes. Meaning, if the description were moderate sedation 30 mins, then the above rule would apply, but because it is worded "first 30 minutes" then any duration of mod sed would qualify. I can't find anything on CMS or AAPC (may not be looking hard enough) but I did find something on this site (http://www.beckersasc.com/asc-codin...ard-of-national-medical-billing-services.html), but not sure if it's a trustworthy source. Also, did not find the citation of their source (AMA) to have stated this, and even if they have, what is their source? Any insight greatly appreciated! I'm leaning toward having to meet 16 mins, just based on the lack of info out there, and using the standard time guidelines in the CPT, however, I do think that a provider could easily appeal something like this if not written specifically in a policy. Thoughts?