Project Summary/Abstract: This proposal responds to AHRQ’s Special Emphasis Notice (NOT-HS-16-011)
highlighting their ongoing interest in receiving applications related to innovative primary care research.
Inequitable access to high-quality primary care is one factor contributing to disparities in ambulatory care-
sensitive health conditions. As primary care changes rapidly to include nurse practitioners (NPs), limited
evidence suggests NPs as a potential mechanism for improving access to primary care. Compared to
physicians, NPs are more likely to treat patients of color, patients covered by Medicaid, and uninsured patients.
This proposed research will provide the first empirical evidence quantifying changes in access to primary
care – particularly for patient populations historically facing access challenges – after group practices employ
an NP. To do so, we propose using a database of all-payer claims and electronic health record data with a
nationwide sample of primary care clinicians. This dataset allows us to overcome three data challenges that
have hindered research on this topic. First, we accurately observe who provided health care services – which
is frequently distinct from who billed for the care. Second, we observe scheduling data, allowing us to construct
objective measures of access such as visit wait time and share of visits provided to new patients. Third and
finally, we observe all care provided by clinicians within our sample, regardless of payer status – allowing us to
compare measures of access across patient populations (i.e., access for Medicaid patients compared to
commercially-insured patients). Dr. Neprash (PI) has access to and has published extensively with the
proposed data source, including work focused on primary care NPs.
In Aim 1, we will quantify changes in access to care for new patients, after an NP joins a primary care
practice. Outcomes include the share of visits provided to new patients (i.e., those not previously treated at the
practice), with a particular focus on new Medicaid or uninsured patients and new patients self-identifying as
Black, Indigenous, and people of color.
In Aim 2, we will quantify overall changes in access to and convenience of care, after an NP joins a
practice. Outcomes include visit wait time (i.e., days elapsed between visit scheduling and visit occurrence),
the share of visits provided on a walk-in basis, and the share of visits provided on evenings and weekends.
This pilot study will provide the first evidence on how access to care – particularly for AHRQ priority
populations – changes when primary care practices employ a nurse practitioner. As NPs become increasingly
prevalent within primary care practices, it is crucial to understand the role they play in potentially expanding
access to primary care services and providing high-quality, efficient care. This small grant proposal represents
the first step in a broader research agenda of understanding the roles that NPs play in reducing health