My CPT book gives good info in the front. There are three things to remember, once you have all of the elements/levels.
Key Components = History, exam, medical decision-making.
1. For these categories, ALL THREE of the key components must meet or exceed the stated requirements to qualify for the level of E&M service: New patient office, hospital observation services, initial hospital care, office consultations, initial inpatient consultations, emergency department services, initial nursing facility care, new patient domiciliary care, and new patient home.
2. For these categories, TWO OUT OF THREE of the key components must meet or exceed the stated requirements to qualify for the level of E&M service: established patient office, subsequent hospital care, subsequent nursing facility care, established patient domiciliary care, established patient home.
3. When counseling and/or coordination of care is more than 50% of the time spent, then time is the key or controlling factor to choose a level of E&M service (time must be documented).
Now, how does this look in real life? My CPT book has nice charts in the front, but here we go.
1. New patient office: Detailed History, Detailed Exam, (so far, we're looking at a 99203). Now if the MDM is straightforward, we drop down to a 99201 or 99202, because ALL THREE components were not at the level for 99203. If MDM is low, moderate, or high, we get to keep the 99203. We can't get better than that because of the detailed level of the first two key components.
2. Established patient office: Detailed History, Detailed Exam. We're already at a 99214, and since we only need two out of three of the key components, that's what we get, we don't even have to go further. MDM can be any level, again, because it's only 2/3.
3. Established patient office: Doctor spends 30 minutes with patient discussing his diagnosis of (whatever), his treatment options, etc. Doctor does a 15 minute exam. Total time spent in counseling was 30 out of 45 minutes, so time is the controlling factor. That gives us 99215.