In Reply: The purpose of our study was to assess whether differences in income between male and female physicians present in the late 1980s are still present today. We found that gender differences in physician earnings have not substantively changed in 25 years. Dr Ambati notes that physician earnings come from a number of sources (eg, relative value units, benefit packages), which is true. However, our estimates of income from the Current Population Survey (CPS) (https://www.census.gov/cps/data/) were designed to capture all sources of labor earnings. While the CPS does not break down labor earnings by source, most if not all of these sources should be included. And if any were missing, we have no reason to suspect that any items that are not reported differ systematically by gender in ways that could explain the persistent male-female earnings gap.
Seabury, Seth A., Amitabh Chandra, and Anupam B. Jena. "Gender Income Disparities Can Be Explained by Alternative Factors—Reply." JAMA Internal Medicine 174.5 (May 2014): 822-823.