The AHRQ Evidence-based Practice Center (EPC) Program supports healthcare quality by providing the best available evidence on medications, devices, and healthcare services to help healthcare professionals, patients, policymakers, and healthcare systems make informed and evidence-based healthcare decisions. Primary care research supports the overall AHRQ mission of producing evidence to make healthcare safer, higher quality, more accessible, equitable, and affordable, and to work within the U.S. Department of Health and Human Services and with other partners to make sure that the evidence is understood and used. Identifying gaps in primary care research can inform future studies and outline areas that need to be addressed to inform clinical practice to improve the Nation's overall health and well-being.

To identify primary care gaps, the EPC Program examined all reviews conducted by an EPC in calendar years 2019–2021 that addressed a research topic in primary care. AHRQ defines primary care research as:

• Research conducted in a primary care setting
• Research conducted by or about primary care clinicians
• Research on a topic integral to the primary care setting

Identified reports are presented in this report in descending order, by date. The purpose, key messages, and evidence gaps identified in each review are summarized. Evidence gaps are organized by population, intervention, study design, and outcomes to facilitate ease of use. Detailed descriptions of the gaps are also available in the original report as provided in hyperlinks.

A thematic analysis of the identified primary care research gaps revealed the following:

• Study population. Improved recruitment is needed for older adults, individuals with pain-related diseases and chronic pain conditions (e.g., neuropathic pain, chronic migraine), individuals with comorbidities, individuals of diverse races and ethnicities (e.g., non-White individuals), and the medically underserved (e.g., rural populations, individuals with lower socioeconomic status).
• Interventions. Research needs to provide more details about the development and implementation of interventions (e.g., program structure, coordination, delivery, accessibility, acceptability, participant cost). 
• Study design. In general, longer followup periods, study expansion to multiple sites, and the recruitment of larger sample sizes can help address evidence gaps.
• Outcomes. More research should examine outcomes assessing quality of life, functionality, and others which are patient-centered (e.g., patient engagement). 

The primary care gaps identified in the following pages are provided to inform research funders, researchers, and policymakers about the types of questions that need to be addressed and the types of studies necessary to address these questions. 

Carr A, Niebuhr D, Alford C, Chang C, Banez L, Iyer S, Wittenberg K, Zhan C, O'Malley P, Umscheid CA. AHRQ EPC Program Research Gaps Summary: Primary Care. Methods Research Report. AHRQ Publication No. 22-EHC017. Rockville, MD: Agency for Healthcare Research and Quality; March 2022. DOI: https://doi.org/10.23970/AHRQEPCGAPSPRIMARYCARE. Posted final reports are located on the Effective Health Care Program search page.