Using the National Provider Identification File as the Sampling Frame for a Physician Survey

• Activity Number: 616
• Type: Contributed
• Date/Time: Thursday, August 7, 2014 : 8:30 AM to 10:20 AM
• Sponsor: Survey Research Methods Section
• Author(s): Jay Clark*+ and Ralph Digaetano
• Companies: Westat and Westat
• Keywords: Sample frame ; coverage ; physicians ; sample design ; estimation

Abstract

For many years the American Medical Association (AMA) Masterfile has served as the standard source of sample frames for physician surveys. Its primary advantages are high coverage and some useful auxiliary variables for sampling and estimation. However, contact information provided is often out-of-date, and some physicians have no contact data provided, adding to survey nonresponse. An alternative source for the frame was used to conduct a recent survey of physicians in the specialties of Family Medicine and Internal Medicine. The frame was derived from the National Provider Identifier (NPI) file of individual health care providers maintained by the Centers for Medicare and Medicaid Beneficiaries (CMS) as part of the National Plan and Provider Enumeration System (NPPES). The results are promising in terms of coverage provided, and contact information was more up-to-date than previously experienced with the AMA file. Nevertheless, there were some drawbacks as well. This paper discusses these findings and draws comparisons to surveys where the AMA file was used as the sample frame. Some strategies for enhancing the usefulness of the NPI file are also considered.