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It used to be so simple: You made an appointment with a doctor and would almost certainly see an MD, someone who spent four years in medical school and then had at least three years of additional training, usually in a hospital.

But today you’re likely to encounter a veritable alphabet soup of health-care degrees: DO, PA, NP and ND, to name a few. Who are all these people? What training do they have? Which one is best for you? And where’s your good-old MD, anyway?

The truth is, you may not always need a traditional physician — and may have a difficult time finding one. The United States is short on doctors, especially those practicing primary care, who typically earn less than specialists. We now have fewer primary-care physicians per person than many other developed nations. Canada, for example, has 1.2 per 1,000 people; the United States, just 0.3.

Because there are fewer primary-care doctors, it’s more difficult to get an appointment. The average wait time for a new patient in a big city to see a family-medicine physician, for example, is now 29 days, compared with 19.5 days in 2014, according to physician recruiting firm Merritt Hawkins.

At the same time, doctors today are feeling pressure to work faster. Because of competitive forces in the marketplace, including many hospitals buying up physician practices, doctors are now more likely to work for large networks than for themselves. And those employers often set daily patient quotas — 16 to 25 per day is typical — that can limit your time with a doctor.

That time crunch, combined with growing demands to document all their encounters in often cumbersome electronic health records, is taking a toll on doctors.

More than half of primary-care doctors report feeling burned out, according to a 2017 Medscape survey. And that could undermine the care they provide, make them less willing to work collaboratively with patients and drive even more out of the profession.

A team of providers

Enter “advanced practice providers.” These are the NPs (nurse practitioners) and PAs (physician assistants) you may run into at a doctor’s office.

They don’t have as much training as MDs, but they are licensed to do many of the same things. And their ranks are growing fast. The share of physicians with these clinicians on their team has risen from 25 percent in 1999 to more than 60 percent now.

But is seeing one of them as good as seeing a medical doctor? In most cases, yes, says Ateev Mehrotra, an associate professor of health-care policy at Harvard Medical School.

His January 2017 study in the journal Medical Care found that practices with more NPs and PAs had fewer specialist referrals, hospitalizations and ER visits. And other research has found that when it comes to high blood pressure, diabetes, respiratory infections and other common problems, there’s little difference in treatment from MDs and advanced practice providers.

The team approach is also efficient, allowing each clinician to focus on what he or she does best. And it can mean shorter wait times and better patient education, according to a 2016 analysis by the Agency for Healthcare Research and Quality.

In addition to NPs and PAs, you may also be more likely to encounter other health-care professionals now.

They include reputable ones, such as doctors of osteopathic medicine (DOs). Their education is similar to an MD’s, with special training in muscle and skeletal issues, and their numbers have been growing.

But you may also encounter some more-controversial providers, such as naturopathic doctors, or NDs.

A Consumer Reports guide, at cr.org/healthproguide, explains who’s who, gives advice on how to get the most of your precious time with each of them and identifies those you should consider steering clear of.

 Copyright 2018, Consumer Reports Inc.

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