Nurse practitioners (NPs) represent the fastest growing segment of the U.S. primary care workforce. Surveys of primary care NPs can help to better understand the care NPs deliver across different health care settings, the factors that impact NP job satisfaction and burnout, and the structural capabilities required to support their practice. The purpose of this article is to provide an overview of national sampling frames that can be used by researchers interested in surveying or studying the U.S. primary care NP workforce. We conducted an environmental scan and review of published literature on the NP workforce to identify data sources that can be used to sample primary care NPs. In this article, we 1) identify the data elements needed to develop a NP sampling frame and 2) describe national datasets that can be used to sample primary care NPs, including the strengths and weaknesses of each. This information is intended to facilitate research on the primary care NP workforce to inform practice and policy.
Keywords: nurse practitioners, primary health care, surveys and questionnaires, workforce
National Sampling Frames for Primary Care Nurse Practitioners
Here, we provide an overview of each sampling frame identified in our search. Details about each sampling frame, including strengths, weaknesses, and cost information, are summarized in Table 2.
Table 2.
Overview of National Sampling Frames for Nurse Practitioners
Sampling Frame Description Cost Strengths Weaknesses
National Plan and Provider Enumeration System (NPPES) The NPPES Downloadable File, updated monthly, provides a list of national provider identifiers (NPIs). The file includes provider taxonomy codes for identification of provider type and specialty, primary business address (mailing address, phone number), and secondary addresses. Free • Searchable database
• Taxonomy codes allow for identification of NP specialty • Provider taxonomy codes are self-reported
• No formal effort to keep provider contact information up to date
National Council of State Boards of Nursing (NCSBN) Nursys Database National database for verification of nurse licensure, discipline, and practice privileges for RNs, LPN/LVNs and APRNs licensed in participating jurisdictions. Requires proposal submission and approval from NCSBN research department to obtain data. Free • Central repository for NP licensure data across multiple states • APRN data only collected for 27 states
• Mailing address is the only contact information consistently captured across state licensing boards
• No specialty information
American Nurses Credentialing Center (ANCC) Nurse Practitioner Certification Data List of nationally certified NPs obtained annually from state boards of nursing, including certifications in primary care and acute care in various patient populations (adult, family, pediatric, etc.). Free • Comprehensive list of NPs certified through ANCC • NP practice setting may not match certification; not all certified NPs are currently practicing
• The data is not widely available to researchers
American Association of Nurse Practitioners (AANP) National Nurse Practitioner Database Database of nationally certified NPs. Through the Survey Question Procurement Program (SQPP), researchers have the opportunity to add up to 5 questions to AANP’s annual survey and receive the raw data and accompanying demographic data already included on the survey (certifications, gender, state, work setting, and self-reported clinical focus). Cost varies based on number of questions added to AANP survey. See SQPP website for details. • Comprehensive data on nationally certified NPs obtained annually from state boards of nursing • Data only available through SQPP
Drug Enforcement Agency (DEA) Registrant File File of all clinicians who have DEA registration to prescribe controlled substances; can be purchased from the National Technical Information Service (NTIS). Includes provider name, provider type (e.g., NP, physician, physician assistant), DEA registration number, drug schedules handled by the provider, and business address. Cost to download raw data varies based on number of data users and frequency of data updates (files are updated daily, weekly, monthly, or quarterly). Contact NTIS for details. • The majority of NPs have DEA registration and are represented in the DEA registrant file • Business address is the only contact information available
• No specialty information
Physician Compare National Downloadable File Lists providers that participate in the Medicare program. Data includes provider name, NPI, graduation year (medical school or other), practice name, group practice ID, practice street address, and practice phone number. Free • Updated twice monthly
• Verified with Medicare claims • Practice street address and practice telephone are the only contact information available
• Excludes NPs not enrolled in Medicare
• No specialty information
Nurse Practitioner Masterfile List of state-licensed NPs available through Medical Marketing Service (MMS). Data includes provider practice locations, provider contact information (mailing address, phone number, email), and specialty information. Cost for provider phone/mailing list varies based on number of records and variables purchased; cost of email broadcasts varies by size of target audience and number of sends. Contact MMS for details. • Updated monthly
• Can be used to sample NPs by specialty at the national level • NP data has not been validated
IQVIA OneKey (SK&A) Health care industry database maintained by IQVIA that collects data on health care providers and practices across the U.S. Data includes provider name, practice name and location, contact information, network affiliation, state license number, and NPI. Cost varies based on number of records and variables purchased. Contact IQVIA for details. • Contains information on nearly the entire population of ambulatory-based providers in the U.S.
• Frequently updated through automated and manual processes
• Includes information about patient volume, number of providers, site specialty, and ownership that is not available elsewhere • NP data has not been validated