That growth was uneven, however, and largely dependent on a doctor’s sex, specialty, and where they practice, the survey showed.

More than 19,200 doctors in more than 27 specialties responded to the largest survey of doctor salaries in the U.S. The survey sample represents about 2% of the almost 1 million doctors in the United States.

The survey was conducted online between Dec. 20, 2016, and March 7, 2017.

In general, the survey found that specialists are paid about 50% more than primary care doctors, which creates an average pay gap of about $100,000 a year. Specialists report making about $316,000 annually, compared with $217,00 for primary care doctors.

Pay increased 10% or more for seven specialties last year:

• Plastic surgery (24%)
• Allergy and immunology (15%)
• Ear, nose, and throat (13%)
• Ophthalmology (12%)
• Pulmonology (11%)
• Orthopedics (10%)
• Pathology (10%)

Pay was flat for primary care doctors, internists, and pediatricians, the survey showed.

Which doctors make the most money? The survey found orthopedists and plastic surgeons were the highest-paid specialists, earning $489,000 and $440,000, respectively. Cardiologists came in third, at $410,000 a year.

By contrast, pediatricians earn less than half that much, reporting annual incomes of $209,000. Family medicine doctors make about $209,000 a year. Endocrinologists are the third lowest-paid group, making $220,000 a year.

Rural areas, particularly those with critical shortages of doctors, offered the best pay.

That finding aligns with a 2005 study by the Center for Studying Health System Change, which found that doctors in rural or sparsely populated areas earn about 13% more than those in other states. The catch is that rural doctors also work longer hours.

The highest-earning states for MDs in 2017 are:

• North Dakota ($361,000)
• South Dakota ($346,000)
• New Hampshire ($337,000)
• Alaska ($259,000)

Doctors earn less where there is an abundance of medical expertise. States with the lowest pay were:

• Delaware ($268,000)
• Rhode Island ($261,000)
• New Mexico ($261,000)
• Maryland ($260,000)
• Washington, D.C. ($235,000)

Female doctors still earn less than their male counterparts, but the Medscape survey found signs that the gap may be narrowing.

In 2017, they earned about 16% less than men in the profession, down about 3% since 2012. On average, female MDs reported average annual earnings of $197,000, compared with $229,000 for men.

This disparity was particularly wide in the specialties. Female specialists made about 37% less than their male colleagues — a divide that docks their pay about $100,000 a year. Women in medical specialties reported average annual incomes of $251,000, compared with $345,000 for men.

One driving factor may be that female doctors are more likely to work in hospitals or physician groups, and self-employed doctors make more money.

Several lower-paying specialties — like pediatrics, psychiatry, and family medicine — have higher concentrations of women, which also might explain some of the difference.

For the first time, the survey asked doctors to identify their race and ethnicity, and as is the case in other professions, African-American, Hispanic, and Asian MDs reported that they earn less than their white counterparts.

On average, white doctors make about $303,000 a year, compared with Hispanic doctors ($271,000), African-Americans ($262,000), and Asians ($283,000).

That finding is in line with a 2016 study that found that white male doctors in the U.S. earned as much as 35% more than black doctors, even after accounting for specialty, experience, number of hours worked, and the number of Medicaid patients they treated.