If you want to see your primary care physician the same day you call for an appointment, you may have to pay for it. A small but growing number of doctors are moving into concierge medicine.

Once restricted to the rich and famous, who paid tens of thousands of dollars for a 24/7 on-call physician, the practice model has evolved over the past 20 years. Today’s concierge medical service is more widely available and affordable. About 12,000 physicians have such practices, and the average annual fee to become a member of a concierge practice is between $1,500 to $2,400 ($125 to $200 a month), according to Concierge Choice Physicians, the nation’s second-largest concierge management company.

Generally, a concierge physician will have between 150 and 600 patients, while a traditional practice might have up to 5,000 patients. Appointments start on time and may last 30 minutes to an hour, depending on patient needs, says Wayne Lipton, managing partner at Concierge Choice Physicians. Compare that with the 18-minute wait time and 20-minute average visit at a traditional practice.

Doctors as well as patients can be frustrated by rushed appointments. “First and foremost, primary care physicians want an ongoing relationship with patients,” says Gary LeRoy, president of the American Academy of Family Physicians. “But we see doctor burn out in large part due to the administrative complexity of practicing medicine. Insurance forms, prior authorization, billing, not to mention trying to see upward of 30 patients a day and constantly watching the clock gets between the doctor and patient relationship,” he says.

No wonder doctors are eyeing other arrangements. (In addition to concierge care, some doctors are turning to a system called direct primary care, in which they reduce overhead and paperwork by declining to participate in insurance plans and in government programs such as Medicare.) But concierge care offers doctors benefits other than improved patient relations: The membership fees provide an additional, stable revenue stream; physicians might earn more money while seeing fewer patients.

Some patients love the idea of concierge care. Chicago attorney Mike Philippi has seen his concierge physician for decades. “Not only do I get an annual comprehensive physical, but I can access him by text message and have as many appointments as I want. My doctor is a primary care quarterback who is quick to say, ‘That’s not my area of expertise,’ but gives me a vetted referral. It’s easy, efficient and I like the notion of one gatekeeper, especially if you have multiple medical issues.”

But for existing patients, a switch can be jarring and unwelcome. In 2016, Ruth Knox, 81, of Annapolis, Md., received a letter informing her that her primary care physicians were transitioning to a “hybrid” concierge model. While current patients would continue to be seen, the doctors were offering a concierge membership that included an annual comprehensive screening exam, same-day or next-day appointments, longer office visits, private office telephone number, round-the-clock physician availability, and a portable USB with medical information. Cost: $2,100 a year. She opted not to take the concierge coverage and wound up leaving the practice.

If your physician is transitioning to a concierge practice or you’re considering joining one, here are some questions to ask.

Do I really need a concierge practice? Though you may be a bigger fish in a smaller pond, for patients who are relatively healthy and don’t see the doctor more than once a year or so, membership may not be necessary. Assessing your health and your stage in life is an important consideration. “It’s a good choice for those with more disposable income than disposable time,” Philippi says. But Knox, a retired special education teacher, says, “I have wonderful health coverage and get everything I want and need for little money. I don’t want to pay extra.”

What is included in membership? Is an annual exam included? What about office visits, lab work, tests, medicine and/or referrals? Other benefits may include same-day/next-day appointments for acute issues; after-hours contact information via phone, email or text; home visits; and hospital care.

How does billing work? Concierge practices generally continue to accept and bill insurance and/or Medicare, so expect to have a co-pay as you would with any other primary care physician. Also, be prepared to pay for the membership fee out of your own pocket, as it is not covered by insurance or Medicare.

Will I see my concierge doctor every time I make an appointment? As more physicians merge their practices into large groups with other doctors and nurse practitioners, this becomes an important member benefit. Patients should be confident that they will generally see their chosen doctor when they make an appointment — not whichever provider has availability.

What happens if I decline a concierge option with my current doctor? Lipton told me by email that in a group practice or in a hybrid practice, the patient may be able to remain at the practice, either with their doctor or another provider. But be prepared for less access to your physician and possibly shorter visits. This is what happened to Knox. After her physician went full-time concierge, Knox could only get an appointment with the nurse practitioner. “I was being squeezed and knew I had to start looking for someone new,” she says.

Before I decide to stay or leave, may I speak to my doctor? “As a patient and a physician, I would want to have that conversation face-to-face or discuss at my next appointment,” LeRoy said. “Don’t assume the corporation is speaking for the doctor. Be prepared to discuss your personal situation.” Knox says her one regret is she did not bring up the concierge switch with her physician before the situation became untenable.

If I leave, can you recommend a new physician? According to the American Medical Association’s ethics guidelines, a doctor switching to concierge care must help patients who choose not to remain with the practice find a new physician. So, your current physician already may have made arrangements with colleagues open to accepting patients. If it’s unfeasible to transfer your care to another local doctor, the AMA guidelines say, your physician should continue to treat you under the terms of your health insurance policy until you can find a replacement.

When conducting your search, don’t forget about local hospitals. “A vast majority of hospitals do have a care network for qualified PCPs in area. Call and ask for who is on their list, taking new patients, accepts my insurance and is close to me,” LeRoy says.

Knox considered recommendations from friends and online ­reviews before settling on a non-concierge family practice about 20 minutes from home that she’s very happy with. “It’s a cozy practice with a nice staff. The doctor was congenial, but also got down to core issues I’m dealing with and dealt with them right away. I realized I wasn’t getting that before,” she says.

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