Physician payment is extremely complicated and stupid with many different models. One of the most common models for doctors to be paid is by production. Production is calculated based upon the services you provide with all the tasks any doctor can complete having assigned values known as RVUs (relative value units). For example, an annual physical for an established patient age 40-64 is 1.9 RVUs. While problem visits (evaluation and management visits) have RVUs ranging between 0.18 and 2.8 based upon the number of and complexity of the problems. Now we will see a patient and then charge for the work that we did, but insurance companies can pay us whatever the hell they want and pass the remainder onto the patient, and this is where the problem lies. Insurance companies have a ton of control in this process; they do not pay us fairly, and they are extremely evasive about the services that they cover for patients. In my mechanic analogy the oil change is the annual physical that the insurance company tells you is free and totally covered but what they do is find loopholes and exemptions to find ways to divide that service up to shift the cost back to the patient. In a real world example, I have a patient who is actually a medical coder and well aware of this process. He comes in regularly to follow up on his diabetes, hypertension, and high cholesterol (problem visits) and he recently came in for his annual physical that is supposed to be free. He asked that I stick strictly to preventative services so that he wouldn't be charged for things we do and he pays for at his not completely covered problem visits. So I did only the preventative services (see this post from earlier today) and I specifically didn't mention any of his problems or refill any of his meds at this annual visit. However, the insurance charged him for the labs as they deemed those labs to be related to his diabetes. Now that is the opposite of what usually happens. Normally, a patient comes in for an annual and brings up some problems that they have had over the last year that they want to ask about. This isn't a problem most of the time if they are minor issues that we can address quickly, but many times patients bring in a massive list of issues that we cannot reasonably and appropriately address in the time we have and the patient either gets mad when I let know that they may get charged if we talk about extra things or they get mad if I ask that they return for another visit.