US Primary Care Workforce Growth: A Decade of Limited Progress, and Projected Needs Through 2040.

BACKGROUND: Despite efforts to mitigate a projected primary care physician (PCP) shortage required to meet an aging, growing, and increasingly insured population, shortages remain, compounded by the COVID-19 pandemic, growing inequity, and persistent underinvestment. OBJECTIVE: We examined primary care workforce trends over the past decade and revisited projected primary care clinician workforce needs through the year 2040. DESIGN AND PARTICIPANTS: Using data from the AMA Masterfile and Medical Expenditure Panel Survey (MEPS), we analyzed trends in the number of primary care physicians (PCPs) and in outpatient PCP visits by age and gender over the past decade. We then used the Medicare PECOS and Physician & Other Practitioners datasets to identify nurse practitioners (NPs) and physician assistants (PAs) in primary care. MEASURES: Using these baseline clinician enumerations and projected population growth estimates from the US Census Bureau for the years 2020-2040, we calculated estimated primary care workforce needs by 2040. KEY RESULTS: The effects of aging and population growth and baseline shortages in the primary care workforce call for significant increases in the primary care workforce to accommodate rising demands. Office visits to primary care clinicians are projected to increase from 773,606 in 2020 to 893,098 in 2040. We project a need for an additional 57,559 primary care clinicians by 2040. CONCLUSIONS: Workforce shortages in primary care continue to expand due to population aging, growth, and heightened rates of clinician burnout & egress.

A Few Doctors Will See Some of You: The Critical Role of Underrepresented in Medicine (URiM) Family Physicians in the Care of Medicaid Beneficiaries.

PURPOSE: Despite being key to better health outcomes for patients from racial and ethnic minority groups, the proportion of underrepresented in medicine (URiM) physicians remains low in the US health care system. This study linked a nationally representative sample of family physicians (FPs) with Medicaid claims data to explore the relative contributions to care of Medicaid populations by FP race and ethnicity. METHODS: This descriptive cross-sectional study used 2016 Medicaid claims data from the Transformed Medicaid Statistical Information System and from 2016-2017 American Board of Family Medicine certification questionnaire responses to examine the diversity and Medicaid participation of FPs. We explored the diversity of FP Medicaid patient panels and whether they saw ≥150 beneficiaries in 2016. Using logistic regression models, we controlled for FP demographics, practice characteristics, and characteristics of the communities in which they practiced. RESULTS: Of 13,096 FPs, Latine, Hispanic, or of Spanish Origin (LHS) FPs and non-LHS Black FPs saw more Medicaid beneficiaries compared with non-LHS White and non-LHS Asian FPs. The patient panels of URiM FPs had a much greater proportion of Medicaid beneficiaries from racial and ethnic minority groups. Overall, non-LHS Black and LHS FPs had greater odds of seeing ≥150 Medicaid beneficiaries in 2016. CONCLUSIONS: These findings clearly show the critical role URiM FPs play in caring for Medicaid beneficiaries, suggesting physician race and ethnicity are correlated with Medicaid participation. Diversity in the health care workforce is essential for addressing racial health inequities. Policies need to address problems in pathways to medical education, including failures to recruit, nurture, and retain URiM students.

Small Independent Primary Care Practices Serving Socially Vulnerable Urban Populations.

PURPOSE: This mixed methods study sought to describe the extent to which family physicians in urban communities serve socially vulnerable patients and to better understand their practices, their challenges, and the structural supports that could facilitate their patient care. METHODS: We conducted a quantitative analysis of questionnaire data from 100% of US physicians recertifying for family medicine from 2017 to 2020. We conducted qualitative analysis of in-depth interviews with 22 physician owners of urban, small, independent practices who reported that the majority of their patients were socially vulnerable. RESULTS: In 2020, in urban areas across the United States, 19.3% of family physicians served in independent practices with 1 to 5 clinicians, down from 22.6% in 2017. Nearly one-half of these physicians reported that >10% of their patients were socially vulnerable. Interviews with 22 physicians who reported that the majority of their patients were socially vulnerable revealed 5 themes: (1) substantial time spent addressing access issues and social determinants of health, (2) minimal support from health care entities, such as independent practice associations and health plans, and insufficient connection to community-based organizations, (3) myriad financial challenges, (4) serious concerns about the future, and (5) deep personal commitment to serving socially vulnerable patients in independent practice. CONCLUSIONS: Small independent practices serving vulnerable patients in urban communities are surviving because deeply committed physicians are making personal sacrifices. Health equity-focused policies could decrease the burden on these physicians and bolster independent practices so that socially vulnerable patients continue to have options when seeking primary care.

The Disproportionate Impact of Primary Care Disruption and Telehealth Utilization During COVID-19.

PURPOSE: The COVID-19 pandemic not only exacerbated existing disparities in health care in general but likely worsened disparities in access to primary care. Our objective was to quantify the nationwide decrease in primary care visits and increase in telehealth utilization during the pandemic and explore whether certain groups of patients were disproportionately affected. METHODS: We used a geographically diverse primary care electronic health record data set to examine the following 3 outcomes: (1) change in total visit volume, (2) change in in-person visit volume, and (3) the telehealth conversion ratio defined as the number of pandemic telehealth visits divided by the total number of prepandemic visits. We assessed whether these outcomes were associated with patient characteristics including age, gender, race, ethnicity, comorbidities, rurality, and area-level social deprivation. RESULTS: Our primary sample included 1,652,871 patients from 408 practices. During the pandemic we observed decreases of 7% and 17% in total and in-person visit volume and a 10% telehealth conversion ratio. The greatest decreases in visit volume were observed among pediatric patients (-24%), Asian patients (-11%), and those with more comorbidities (-9%). Telehealth usage was greatest among Hispanic or Latino patients (17%) and those living in urban areas (12%). CONCLUSIONS: Decreases in primary care visit volume were partially offset by increasing telehealth use for all patients during the COVID-19 pandemic, but the magnitude of these changes varied significantly across all patient characteristics. These variations have implications not only for the long-term consequences of the COVID-19 pandemic, but also for planners seeking to ready the primary care delivery system for any future systematic disruptions.

Post-COVID Conditions in US Primary Care: A PRIME Registry Comparison of Patients With COVID-19, Influenza-Like Illness, and Wellness Visits.

PURPOSE: COVID-19 is a condition that can lead to other chronic conditions. These conditions are frequently diagnosed in the primary care setting. We used a novel primary care registry to quantify the burden of post-COVID conditions among adult patients with a COVID-19 diagnosis across the United States. METHODS: We used the American Family Cohort, a national primary care registry, to identify study patients. After propensity score matching, we assessed the prevalence of 17 condition categories individually and cumulatively, comparing patients having COVID-19 in 2020-2021 with (1) historical control patients having influenza-like illness in 2018 and (2) contemporaneous control patients seen for wellness or preventive visits in 2020-2021. RESULTS: We identified 28,215 patients with a COVID-19 diagnosis and 235,953 historical control patients with influenza-like illness. The COVID-19 group had higher prevalences of breathing difficulties (4.2% vs 1.9%), type 2 diabetes (12.0% vs 10.2%), fatigue (3.9% vs 2.2%), and sleep disturbances (3.5% vs 2.4%). There were no differences, however, in the postdiagnosis monthly trend in cumulative morbidity between the COVID-19 patients (trend = 0.026; 95% CI, 0.025-0.027) and the patients with influenza-like illness (trend = 0.026; 95% CI, 0.023-0.027). Relative to contemporaneous wellness control patients, COVID-19 patients had higher prevalences of breathing difficulties and type 2 diabetes. CONCLUSIONS: Our findings show a moderate burden of post-COVID conditions in primary care, including breathing difficulties, fatigue, and sleep disturbances. Based on clinical registry data, the prevalence of post-COVID conditions in primary care practices is lower than that reported in subspecialty and hospital settings.

The Association of Mobility, Social Deprivation, and Pediatric Primary Care Outcomes in Community Health Centers.

OBJECTIVE: To examine how social deprivation and residential mobility are associated with primary care use in children seeking care at community health centers (CHCs) overall and stratified by race and ethnicity. STUDY DESIGN: We used electronic health record open cohort data from 152 896 children receiving care from 15 U S CHCs belonging to the OCHIN network. Patients were aged 3-17 years, with ≥2 primary care visits during 2012-2017 and had geocoded address data. We used negative binomial regression to calculate adjusted rates of primary care encounters and influenza vaccinations relative to neighborhood-level social deprivation. RESULTS: Higher rates of clinic utilization were observed for children who always lived in highly deprived neighborhoods (RR = 1.11, 95% CI = 1.05-1.17) and those who moved from low-to-high deprivation neighborhoods (RR = 1.05, 95% CI = 1.01-1.09) experienced higher rates of CHC encounters compared with children who always lived in the low-deprivation neighborhoods. This trend was similar for influenza vaccinations. When analyses were stratified by race and ethnicity, we found these relationships were similar for Latino children and non-Latino White children who always lived in highly deprived neighborhoods. Residential mobility was associated with lower rates of primary care. CONCLUSIONS: These findings suggest that children living in or moving to neighborhoods with high levels of social deprivation used more primary care CHC services than children who lived in areas with low deprivation, but moving itself was associated with less care. Clinician and delivery system awareness of patient mobility and its impacts are important to addressing equity in primary care.

Variation in Family Physicians' Experiences Across Different Electronic Health Record Platforms: a Descriptive Study.

BACKGROUND: Electronic health records (EHRs) have been connected to excessive workload and physician burnout. Little is known about variation in physician experience with different EHRs, however. OBJECTIVE: To analyze variation in reported usability and satisfaction across EHRs. DESIGN: Internet-based survey available between December 2021 and October 2022 integrated into American Board of Family Medicine (ABFM) certification process. PARTICIPANTS: ABFM-certified family physicians who use an EHR with at least 50 total responding physicians. MEASUREMENTS: Self-reported experience of EHR usability and satisfaction. KEY RESULTS: We analyzed the responses of 3358 physicians who used one of nine EHRs. Epic, athenahealth, and Practice Fusion were rated significantly higher across six measures of usability. Overall, between 10 and 30% reported being very satisfied with their EHR, and another 32 to 40% report being somewhat satisfied. Physicians who use athenahealth or Epic were most likely to be very satisfied, while physicians using Allscripts, Cerner, or Greenway were the least likely to be very satisfied. EHR-specific factors were the greatest overall influence on variation in satisfaction: they explained 48% of variation in the probability of being very satisfied with Epic, 46% with eClinical Works, 14% with athenahealth, and 49% with Cerner. CONCLUSIONS: Meaningful differences exist in physician-reported usability and overall satisfaction with EHRs, largely explained by EHR-specific factors. User-centric design and implementation, and robust ongoing evaluation are needed to reduce physician burden and ensure excellent experience with EHRs.

Exploring the Association Between Physician Continuity of Care and Diagnosing Hypertension.

Context. The American Board of Family Medicine was funded by the Gordon Betty Moore Foundation to study the association between physician continuity of care, a clinical quality measure, and its impact on accurate, timely, efficient, and cost-effective diagnosis of target conditions that contribute to cardiovascular disease. In this exploratory analysis, we used electronic health records data from the PRIME registry to examine the association of continuity with factors leading to a hypertension diagnosis. Objective. 1) to determine the rate and timeliness of hypertension diagnosis, 2) to investigate the number of hypertension-level blood pressure (BP) readings in the 12 months prior to the diagnosis, and 3) to explore the association between physician continuity of care and these variables. Study Design and Population Studied. In this cohort study, we created two patient cohorts. Our prospective cohort consisted of patients who had 2 or more BP readings greater than SBP of 130 or DBP of 80 mm Hg in 2017-2018 and who did not have a hypertension diagnosis prior to the date of the second reading. Our retrospective cohort consisted of patients who had a hypertension diagnosis in 2018-2019. Dataset. Electronic health records extracted from the PRIME registry Outcome Measures. The rate of diagnosis was calculated by dividing the number of patients with a hypertension diagnosis by the number of patients whose BP readings exceeded the thresholds for hypertension per clinical guidelines. We investigated the timeliness of diagnosis by counting the average days between the second reading and the diagnosis dates. We also identified the number of hypertension-level BP readings in the past 12 months for patients diagnosed with hypertension. Results. Of 7,615 eligible patients from 4 pilot practices, the rate of hypertension diagnosis varied from 39.6% (solo practice) to 11.5% (large practice). The average days until diagnosis ranged from 142 days (solo practice) to 247 days (medium practice). Among patients diagnosed with hypertension (n=104,727), 25.7% had 0, 39.8% had 1, 14.7% had 2 and 19.7 had 3 or more hypertension-level BP readings in the 12 months prior to the diagnosis. We found no significant association between physician continuity of care and the rate or timeliness of the hypertension diagnosis. Conclusions. Factors leading to a hypertension diagnosis may be influenced more by other unobserved variables than by physician continuity of care.

Impact of Service-Based Student Loan Repayment Program on the Primary Care Workforce.

PURPOSE: As the average level of medical education indebtedness rises, physicians look to programs such as Public Service Loan Forgiveness (PSLF) and National Health Service Corps (NHSC) to manage debt burden. Both represent service-dependent loan repayment programs, but the requirements and program outcomes diverge, and assessing the relative uptake of each program may help to inform health workforce policy decisions. We sought to describe variation in the composition of repayment program participant groups and measure relative impact on patient access to care. METHODS: In this bivariate analysis, we analyzed data from 10,677 respondents to the American Board of Family Medicine's National Graduate Survey to study differences in loan repayment program uptake as well as the unique participant demographics, scope of practice, and likelihood of practicing with a medically underserved or rural population in each program cohort. RESULTS: The rate of PSLF uptake tripled between 2016 and 2020, from 7% to 22% of early career family physicians, while NHSC uptake remained static at 4% to 5%. Family physicians reporting NHSC assistance were more likely than those reporting PSLF assistance to come from underrepresented groups, demonstrated a broader scope of practice, and were more likely to practice in rural areas (23.3% vs 10.8%) or whole-county Health Professional Shortage Areas (12.5% vs 3.7%) and with medically underserved populations (82.2% vs 24.2%). CONCLUSIONS: Although PSLF supports family physicians intending to work in public service, their peers who choose NHSC are much more likely to work in underserved settings. Our findings may prompt a review of the goals of service loan forgiveness programs with potential to better serve health workforce needs.

The Impact of Interpersonal Continuity of Primary Care on Health Care Costs and Use: A Critical Review.

PURPOSE: Interpersonal continuity has been shown to play an essential role in primary care's salutary effects. Amid 2 decades of rapid evolution in the health care payment model, we sought to summarize the range of peer-reviewed literature relating continuity to health care costs and use, information critical to assessing the need for continuity measurement in value-based payment design. METHODS: After comprehensively reviewing prior continuity literature, we used a combination of established medical subject headings (MeSH) and key words to search PubMed, Embase, and Scopus for articles published between 2002 and 2022 on "continuity of care" and "continuity of patient care," and payor-relevant outcomes, including cost of care, health care costs, cost of health care, total cost of care, utilization, ambulatory care-sensitive conditions, and hospitalizations for these conditions. We limited our search to primary care key words, MeSH terms, and other controlled vocabulary, including primary care, primary health care, family medicine, family practice, pediatrics, and internal medicine. RESULTS: Our search yielded 83 articles describing studies that were published between 2002 and 2022. Of these, 18 studies having a total of 18 unique outcomes examined the association between continuity and health care costs, and 79 studies having a total of 142 unique outcomes assessed the association between continuity and health care use. Interpersonal continuity was associated with significantly lower costs or more favorable use for 109 of the 160 outcomes. CONCLUSIONS: Interpersonal continuity today remains significantly associated with lower health care costs and more appropriate use. Further research is needed to disaggregate these associations at the clinician, team, practice, and system levels, but continuity assessment is clearly important to designing value-based payment for primary care.

Characteristics of Family Physicians Practicing Collaboratively With Behavioral Health Professionals.

Integrating behavioral health into primary care can improve access to behavioral health and patient health outcomes. We used 2017-2021 American Board of Family Medicine continuing certificate examination registration questionnaire responses to determine the characteristics of family physicians who work collaboratively with behavioral health professionals. With a 100% response rate, 38.8% of 25,222 family physicians reported working collaboratively with behavioral health professionals, with those working in independently owned practices and in the South having substantially lower rates. Future research exploring these differences could help develop strategies to support family physicians implement integrated behavioral health to improve care for patients in these communities.

Racial and ethnic disparities in access to primary care during COVID-19.

Context: Early evidence suggests that many patients chose to forgo or delay necessary medical care during the COVID-19 pandemic. Existing and well-documented racial and ethnic disparities in access to care were exacerbated by the pandemic for many reasons, potentially including the additional barriers involved in a rapid shift to telehealth for certain groups of patients. Objectives: 1) Examine changes in primary care visit volume and telehealth during the COVID-19 pandemic. 2) Test for racial and ethnic differences in primary care in-person and telehealth visits during the pandemic relative to pre-pandemic levels. Study design: Longitudinal. Datasets: EHR data including patient visits, procedures, and demographics captured in the American Board of Family Medicine's PRIME Registry. Population studied: 2,966,859 patients seeing 1,477 primary care clinicians enrolled in the PRIME Registry. Outcome measures: 7-day average of weekly visits per clinician, both in-person and telehealth, tracking trends in the volume of care provided before and during the pandemic by patient race/ethnicity. We defined telehealth conversion ratio (TCR) as the number of telehealth visits during the pandemic divided by the total number of pre-pandemic visits. We calculated TCR and visit volume changes from March 15 through the end of 2020 relative to the same period in 2019. Results: During the pandemic we observed decreases of 12% and 22% in the average number of total and in-person visits, respectively, as well as a 10% TCR. Total visits reached a nadir in April 2020 with a 29% decrease from the same point in 2019. Telehealth visits peaked the following week with 23% of that week's total visits, and 139 times more than 2019. Total visits decreased and telehealth visits increased for patients of all races/ethnicities. The magnitude of these changes differed, with Black (5% decline, 15% in-person decline, 10% TCR) and Hispanic (9%, 24%, 15%) patients seeing less of a decrease in total visits than White (12%, 21%, 9%) and Asian (16%, 30%, 14%) patients. Conclusion: Declines in primary care visits during the pandemic were partially offset by an increase in telehealth use. Utilization in our sample suggests less decline in Black and Hispanic patient primary care utilization during the pandemic than expected, in contrast to Asian patients, who demonstrated the largest declines. This metric and these results are novel and foundational for ongoing & further study using other data sources.

Competencies for the Use of Artificial Intelligence in Primary Care.

The artificial intelligence (AI) revolution has arrived for the health care sector and is finally penetrating the far-reaching but perpetually underfinanced primary care platform. While AI has the potential to facilitate the achievement of the Quintuple Aim (better patient outcomes, population health, and health equity at lower costs while preserving clinician well-being), inattention to primary care training in the use of AI-based tools risks the opposite effects, imposing harm and exacerbating inequalities. The impact of AI-based tools on these aims will depend heavily on the decisions and skills of primary care clinicians; therefore, appropriate medical education and training will be crucial to maximize potential benefits and minimize harms. To facilitate this training, we propose 6 domains of competency for the effective deployment of AI-based tools in primary care: (1) foundational knowledge (what is this tool?), (2) critical appraisal (should I use this tool?), (3) medical decision making (when should I use this tool?), (4) technical use (how do I use this tool?), (5) patient communication (how should I communicate with patients regarding the use of this tool?), and (6) awareness of unintended consequences (what are the "side effects" of this tool?). Integrating these competencies will not be straightforward because of the breadth of knowledge already incorporated into family medicine training and the constantly changing technological landscape. Nonetheless, even incremental increases in AI-relevant training may be beneficial, and the sooner these challenges are tackled, the sooner the primary care workforce and those served by it will begin to reap the benefits.

Using Machine Learning to Predict Primary Care and Advance Workforce Research.

PURPOSE: To develop and test a machine-learning-based model to predict primary care and other specialties using Medicare claims data. METHODS: We used 2014-2016 prescription and procedure Medicare data to train 3 sets of random forest classifiers (prescription only, procedure only, and combined) to predict specialty. Self-reported specialties were condensed to 27 categories. Physicians were assigned to testing and training cohorts, and random forest models were trained and then applied to 2014-2016 data sets for the testing cohort to generate a series of specialty predictions. Comparing the predicted specialty to self-report, we assessed performance with F1 scores and area under the receiver operating characteristic curve (AUROC) values. RESULTS: A total of 564,986 physicians were included. The combined model had a greater aggregate (macro) F1 score (0.876) than the prescription-only (0.745; P <.01) or procedure-only (0.821; P <.01) model. Mean F1 scores across specialties in the combined model ranged from 0.533 to 0.987. The mean F1 score was 0.920 for primary care. The mean AUROC value for the combined model was 0.992, with values ranging from 0.982 to 0.999. The AUROC value for primary care was 0.982. CONCLUSIONS: This novel approach showed high performance and provides a near real-time assessment of current primary care practice. These findings have important implications for primary care workforce research in the absence of accurate data.

Trends in the Gender Ratio of Authorship at the Robert Graham Center.

Gender disparities in medical publication have been demonstrated in several specialties. This descriptive bibliometric analysis aims to determine the gender ratio of scholarly authorship at the Robert Graham Center (RGC) over an 11-year period. We examined publications by RGC researchers and assessed first, second, and last author gender. Of 229 publications, 65.5% had a male first author and 34.5% had a female first author. Of the 217 publications with a last author, 13.4% had a female last author. This study aims to inform the broader discussion about authorship gender parity in academic medicine using a one-site case-study approach.

Oral corticosteroid use, obesity, and ethnicity in children with asthma.

Objective: Comorbid asthma and obesity leads to poorer asthma outcomes, partially due to decreased response to controller medication. Increased oral steroid prescription, a marker of uncontrolled asthma, may follow. Little is known about this phenomenon among Latino children. Our objective was to determine whether obesity is associated with increased oral steroid prescription for children with asthma, and to assess potential disparities in these associations between Latino and non-Hispanic white children.Methods: We examined electronic health record data from the ADVANCE national network of community health centers. The sample included 16,763 children aged 5-17 years with an asthma diagnosis and ≥1 ambulatory visit in ADVANCE clinics across 22 states between 2012 and 2017. Poisson regression analysis was used to examine the rate of oral steroid prescription overall and by ethnicity controlling for potential confounders.Results: Among Latino children, those who were always overweight/obese at study visits had a 15% higher rate of receiving an oral steroid prescription than those who were never overweight/obese [rate ratio (RR) = 1.15, 95% CI 1.05-1.26]. A similar effect size was observed for non-Hispanic white children, though the relationship was not statistically significant (RR = 1.10, 95% CI: 0.92-1.33). The interactions between body mass index and ethnicity were not significant (sometimes overweight/obese p = 0.95, always overweight/obese p = 0.58), suggesting a lack of disparities in the association between obesity and oral steroid prescription by ethnicity.Conclusions: Children with obesity received more oral steroid prescriptions than those at a healthy weight, which may be indicative of worse asthma control. We did not observe significant ethnic disparities.

Primary Care Research Priorities in Low-and Middle-Income Countries.

PURPOSE: To identify and prioritize the needs for new research evidence for primary health care (PHC) in low-and middle-income countries (LMICs) about organization, models of care, and financing of PHC. METHODS: Three-round expert panel consultation of LMIC PHC practitioners and academics sampled from global networks, via web-based surveys. Iterative literature review conducted in parallel. Round 1 (pre-Delphi survey) elicited possible research questions to address knowledge gaps about organization and models of care and about financing. Round 2 invited panelists to rate the importance of each question, and in round 3 panelists provided priority ranking. RESULTS: One hundred forty-one practitioners and academics from 50 LMICs from all global regions participated and identified 744 knowledge gaps critical to improving PHC organization and 479 for financing. Four priority areas emerged: effective transition of primary and secondary services, horizontal integration within a multidisciplinary team and intersectoral referral, integration of private and public sectors, and ways to support successfully functioning PHC professionals. Financial evidence priorities were mechanisms to drive investment into PHC, redress inequities, increase service quality, and determine the minimum necessary budget for good PHC. CONCLUSIONS: This novel approach toward PHC needs in LMICs, informed by local academics and professionals, created an expansive and prioritized list of critical knowledge gaps in PHC organization and financing. It resulted in research questions, offering valuable guidance to global supporters of primary care evaluation and implementation. Its source and context specificity, informed by LMIC practitioners and academics, should increase the likelihood of local relevance and eventual success in implementing research findings.

Clinicians' Overestimation of Their Geographic Service Area.

In this study, we evaluated family physicians' ability to estimate the service area of their patient panel-a critical first step in contextual population-based primary care. We surveyed 14 clinicians and administrators from 6 practices. Participants circled their estimated service area on county maps that were compared with the actual service area containing 70% of the practice's patients. Accuracy was ascertained from overlap and the amount of estimated census tracts that were not part of the actual service area. Average overlap was 75%, but participants overestimated their service area by an average of 166 square miles. Service area overestimation impedes implementation of targeted community interventions by practices.

Higher Primary Care Physician Continuity is Associated With Lower Costs and Hospitalizations.

PURPOSE: Continuity of care is a defining characteristic of primary care associated with lower costs and improved health equity and care quality. However, we lack provider-level measures of primary care continuity amenable to value-based payment, including the Medicare Quality Payment Program (QPP). We created 4 physician-level, claims-based continuity measures and tested their associations with health care expenditures and hospitalizations. METHODS: We used Medicare claims data for 1,448,952 beneficiaries obtaining care from a nationally representative sample of 6,551 primary care physicians to calculate continuity scores by 4 established methods. Patient-level continuity scores attributed to a single physician were averaged to create physician-level scores. We used beneficiary multilevel models, including beneficiary controls, physician characteristics, and practice rurality to estimate associations with total Medicare Part A & B expenditures (allowed charges, logged), and any hospitalization. RESULTS: Our continuity measures were highly correlated (correlation coefficients ranged from 0.86 to 0.99), with greater continuity associated with similar outcomes for each. Adjusted expenditures for beneficiaries cared for by physicians in the highest Bice-Boxerman continuity score quintile were 14.1% lower than for those in the lowest quintile ($8,092 vs $6,958; ß = -0.151; 95% CI, -0.186 to -0.116), and the odds of hospitalization were 16.1% lower between the highest and lowest continuity quintiles (OR = 0.839; 95% CI, 0.787 to 0.893). CONCLUSIONS: All 4 continuity scores tested were significantly associated with lower total expenditures and hospitalization rates. Such indices are potentially useful as QPP measures, and may also serve as proxy resource-use measures, given the strength of association with lower costs and utilization.