Primary Care Practice Characteristics Associated With Medical Assistant Staffing Ratios ======================================================================================= * Hector P. Rodriguez * Alena D. Berube * Dorothy Y. Hung * Stephen M. Shortell * Elliott S. Fisher ## Abstract This study characterized adult primary care medical assistant (MA) staffing. National Survey of Healthcare Organizations and Systems (n = 1,252) data were analyzed to examine primary care practice characteristics associated with MA per primary care clinician (PCC) staffing ratios. In 2021, few practices (11.4%) had ratios of 2 or more MAs per PCCs. Compared with system-owned practices, independent (odds ratio [OR] = 1.76, *P* <0.05) and medical group-owned (OR = 2.09, *P* <0.05) practices were more likely to have ratios of 2 or more MAs per PCCs, as were practices with organizational cultures oriented to innovation (*P* <0.05). Most primary care practices do not have adequate MA staffing. Key words: * health workforce * primary health care * organizational culture * health care systems * ownership ## INTRODUCTION Medical assistants (MAs) are among the fastest growing occupations within the US primary care workforce,1 but little is known about organizational factors associated with MA support levels for primary care clinicians (PCCs). Increased accountability for quality of care has led many practices to expand roles for primary care MAs, including health coaching for adults with chronic conditions.2-4 Interprofessional care team approaches rely on robust support from MAs; for example, the teamlet model of primary care recommends 2 MAs per PCC.5 We examine primary care characteristics associated with MA staffing ratios. Past evidence indicates that health care system ownership of primary care practices may impede patient-centered innovation, such as MA role expansion, because they require resources that may not be sufficiently aligned with existing health care system goals or incentives.6 ## METHODS ### Data We analyzed practice survey responses to the second wave of the National Survey of Healthcare Organizations and Systems (NSHOS II), a 52-question survey of a nationally representative sample of non-federal adult primary care physician practices, as defined by the 2020 IQVIA OneKey database. The NSHOS was developed by Dartmouth College, Harvard University, and University of California, Berkeley researchers, and the data have been analyzed extensively in past research.6-9 Surveys were collected from physician leaders and/or practice managers between May 2021 to March 2022. From 1,540 total responses (response rate = 38%), duplicate surveys (n = 137) and surveys with high item non-response (n = 151) were excluded, resulting in an analytic sample of 1,252 practices. [Supplemental Table 1](https://www.annfammed.org/lookup/suppl/doi:10.1370/afm.3100/-/DC1) compares NSHOS II respondent and non-respondent practices. Sampling and non-response weights were used. ### Measures #### Medical Assistant per PCC Staffing Ratio Respondents were asked, “What is the current ratio of medical assistants (MAs) to primary care clinicians in your practice?” and selected from the following response options: (1) We do not employ MAs, (2) Less than 1 MA per clinician, (3) One MA per clinician, (4) Two MAs per clinician, and (5) Three or more MAs per clinician. Given the recommended 2 or more MAs per clinician for the teamlet model of primary care,5 we constructed a binary outcome measure of 2 or more MAs per PCC. #### Practice Ownership Practice ownership was a categorical variable that assessed whether a practice is independent, health system owned, hospital owned, medical group owned, designated as a Federally Qualified Health Center (FQHC), or other. #### Practice Culture Practice culture was assessed with a 7-item measure of “innovation culture.” The questions were informed by qualitative research of the complexity of organizational cultures within and between physician groups10 and the Competing Values Framework of organizational culture.11 Organizational cultures more oriented to innovation have been found to be associated with greater practice adoption of patient engagement strategies and chronic care management processes.6,9 Information about item content ([Supplemental Table 2](https://www.annfammed.org/lookup/suppl/doi:10.1370/afm.3100/-/DC1)), internal consistency reliability ([Supplemental Table 3](https://www.annfammed.org/lookup/suppl/doi:10.1370/afm.3100/-/DC1)), and distributions ([Supplemental Figure](https://www.annfammed.org/lookup/suppl/doi:10.1370/afm.3100/-/DC1)) are detailed in the supplemental materials linked here. Other covariates are described in Table 1 footnotes. View this table: [Table 1.](http://www.annfammed.org/content/22/3/233/T1) Table 1. Primary Care Practice Characteristics, by Medical Assistant to Primary Care Clinician Staffing Ratios ### Analyses Multivariable logistic regression models estimated the association of practice ownership and practice culture with practice use of staffing ratios of 2 or more MAs per PCC, controlling for covariates. ## RESULTS Most adult primary care practices (56.6%) had ratios of 1 MA per PCC, while only 11.4% had ratios of 2 or more MAs per PCCs; 27.6% had ratios of less than 1:1, and 4.3% of practices did not employ MAs (Table 1). In adjusted analyses, compared with system-owned practices, independent (odds ratio [OR] = 1.76, *P* <0.05) and medical group–owned (OR = 2.09, *P* <0.05) practices had significantly greater odds of having ratios of 2 or more MAs per PCC (Table 2). Practices with organizational cultures oriented to innovation (OR = 1.35, *P* <0.05) had greater odds of having ratios of 2 or more MAs per PCC. View this table: [Table 2.](http://www.annfammed.org/content/22/3/233/T2) Table 2. Adjusted Analyses: Practice Characteristics Associated With Medical Assistant per Primary Care Clinician Staffing Ratios ## DISCUSSION Approximately 1 in 10 adult primary care practices have ratios of 2 or more MAs per PCC. Independent practices, medical group–owned practices, and FQHC practices were more likely to have ratios of 2 or more MAs per PCC ratios than practices owned by health care systems. Practice ownership may influence managerial control and physician autonomy to determine staffing levels that enable high-quality, patient-centered primary care.12 Practices with cultures oriented to innovation were also more likely to have staffing ratios of 2 or more MAs per PCC, possibly because they were better able to retain MA staff during the COVID-19 pandemic federal emergency period.13 System-owned practices may opt to hire other staff, including nurses and other non-physician clinicians, instead of staffing 2 MAs per PCC.14 The number of advanced practice clinicians and the extent of non-physician clinicians’ involvement in complex care management processes, however, were not significantly associated with MA per PCC staffing ratios. These findings challenge the perception that MAs are substitutes for other care team members like nurses and behavioral health specialists. Study limitations include a modest response rate, although comparable to large-scale organizational surveys conducted during the pandemic. Clinical and non-clinical efforts were not differentiated, and staffing records were not used to confirm the levels reported. Additional measures of practice culture and burnout could have enriched these analyses and should be examined in future research. Staffing ratios and cultural assessments were both self-reported, so common method bias is another potential limitation. The National Academy of Sciences, Engineering, and Medicine’s Committee on Implementing High-Quality Primary Care recommended greater investment in primary care as a key step toward improving population health.15 Most primary care practices do not have adequate MA support. Ensuring that PCCs have sufficient MA support is a concrete step that payers and organizations can take to support primary care practices. ## Acknowledgments We thank Wendy Yang and Karen Schifferdecker for contributions to survey development, data collection, and research data management. ## Footnotes * Conflicts of interest: authors report none. * [Read or post commentaries in response to this article](https://www.annfammed.org/content/2/3/184/tab-e-letters). * **Funding support:** The research study was funded by the Robert Wood Johnson Foundation (#78479). * [Supplemental materials](https://www.annfammed.org/lookup/suppl/doi:10.1370/afm.3100/-/DC1) * Received for publication August 2, 2023. * Revision received December 18, 2023. * Accepted for publication January 8, 2024. * © 2024 Annals of Family Medicine, Inc. ## References 1. 1.Bureau of Labor Statistics, U.S. Department of Labor. Occupational Outlook Handbook, Medical Assistants. Updated Sep 6, 2023. Accessed Jul 19, 2023. 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