A: An article by DesRoches et al (2015) compared the National Provider and Plan Enumeration System (NPPES), the American Medical Association Masterfile, and the SK&A physician file to evaluate data accuracy. The authors performed this analysis in the context of using the selected datasets for sampling frameworks and counting physicians in a given area. The authors found that while none of the files were perfect, the NPPES contained broader coverage and NPPES and SK&A data had reasonably accurate and current address information. The AMA Masterfile had lower rates of correct address information.
State licensure data are another matter. Some state medical boards require only basic information, including a mailing address for licensing correspondence. Some states collect more robust data through licensure, including multiple practice addresses, and demographic, education, and practice characteristics. Some states conduct regular surveys. States may or may not systematically verify the licensure or survey data.
Different data sources have different limitations. Before using any dataset as a sampling frame or for research, it is essential to understand the data’s purpose and how they are collected, verified, and updated.
A: There are multiple approaches to collecting data and data are often collected for different purposes. As a result, it is important to understand the methodology behind each dataset and its intended use in order to make valid comparisons. For example, the Bureau of Labor Statistics Occupational Employment Statistics collects data from employment surveys; the data count jobs, not workers, and they count employed, not self-employed positions. Professional association masterfiles (eg, AMA, ADA) are based on membership surveys and other sources, and data may not accurately account for professionals that are licensed and practicing in more than one state. State licensure data are self-reported through license applications and renewals, and hinge on the licensees accuracy and timeliness. The National Provider and Plan Enumeration System (NPPES) is a registry of providers that submit Medicare and Medicaid claims; this is an administrative database where the billing address of the provider may not match the provider’s practice location. Health professionals are mobile, some more than others, and change jobs and locations; these moves may not be reflected accurately or in a timely manner.
A: Many states are already collecting health workforce data, with a customized MDS in place to collect any additional data they need for health workforce planning. Some examples of states that are already collecting an MDS include North Carolina, Virginia, New York, Indiana, and Minnesota.
For more information on which states are collecting data, visit our State Health Workforce Data Collection Inventory, or contact HWTAC.
A: The Minimum Data Set (MDS) provides guidelines for collecting basic, minimum, and consistent data on health professionals. These guidelines are not requirements, but they do provide suggestions so that data are collected in a way that is useful for research purposes and comparable across professions and states. Some states ask questions that go beyond the MDS so they can better understand their workforce and answer questions from their policymakers.
The following resources provide information on basic MDS guidelines and going beyond the MDS to ask additional questions, plus examples of data collection instruments from various states.
• Minimum Data Sets Created by National Boards, Councils, and Associations
• The Health Workforce Minimum Data Set (MDS): What You Need to Know (2016)
• Beyond the Minimum Data Set (MDS): What Additional Data Do States Collect on Health Workforce Supply? (2016)
• State Health Workforce Data Collection Inventory (look for states with “Yes” under “Surveys Available”)