The Association of Rural Residence With Surgery and Adjuvant Radiation in Medicare Beneficiaries With Rectal Cancer.

Purpose: Radiation therapy and surgery are fundamental site-directed therapies for nonmetastatic rectal cancer. To understand the relationship between rurality and access to specialized care, we characterized the association of rural patient residence with receipt of surgery and radiation therapy among Medicare beneficiaries with rectal cancer. Methods and Materials: We identified fee-for-service Medicare beneficiaries aged 65 years or older diagnosed with nonmetastatic rectal cancer from 2016 to 2018. Beneficiary place of residence was assigned to one of 3 geographic categories (metropolitan, micropolitan, or small town/rural) based on census tract and corresponding rural urban commuting area codes. Multivariable regression models were used to determine associations between levels of rurality and receipt of both radiation and proctectomy within 180 days of diagnosis. In addition, we explored associations between patient rurality and characteristics of surgery and radiation such as minimally invasive surgery (MIS) or intensity modulated radiation therapy (IMRT). Results: Among 13,454 Medicare beneficiaries with nonmetastatic rectal cancer, 3926 (29.2%) underwent proctectomy within 180 days of being diagnosed with rectal cancer, and 1792 (13.3%) received both radiation and proctectomy. Small town/rural residence was associated with an increased likelihood of receiving both radiation and proctectomy within 180 days of diagnosis (adjusted subhazard ratio, 1.15; 95% CI, 1.02-1.30). Furthermore, small town/rural radiation patients were significantly less likely to receive IMRT (adjusted odds ratio, 0.62; 95% CI, 0.48-0.80) or MIS (adjusted odds ratio, 0.80; 95% CI, 0.66-0.97) than metropolitan patients. Conclusions: Although small town/rural Medicare beneficiaries were overall more likely to receive both radiation and proctectomy for their rectal cancer, they were less likely to receive preoperative IMRT or MIS as part of their treatment regimen. Together, these findings clarify that among Medicare beneficiaries, there appeared to be a similar utilization of radiation resources and time to radiation treatment regardless of rural/urban status.

Internal and Environmental Predictors of Physician Practice Use of Screening and Medications for Opioid Use Disorders.

Medications for opioid use disorder (MOUD) remain highly inaccessible despite demonstrated effectiveness. We examine the extent of screening for opioid use and availability of MOUD in a national cross-section of multi-physician primary care and multispecialty practices. Drawing on an existing framework to characterize the internal and environmental context, we assess socio-technical, organizational-managerial, market-based, and state-regulation factors associated with the use of opioid screening and offering of MOUD in a practice. A total of 26.2% of practices offered MOUD, while 69.4% of practices screened for opioid use. Having advanced health information technology functionality was positively associated with both screening for opioid use and offering MOUD in a practice, while access to on-site behavioral clinicians was positively associated with offering MOUD in adjusted models. These results suggest that improving access to information and expertise may enable physician practices to respond more effectively to the nation's ongoing opioid epidemic.

Rural Disparities in Lung Cancer-directed Surgery: A Medicare Cohort Study.

OBJECTIVE: The primary objective of this study was to determine the influence of rural residence on access to and outcomes of lung cancer-directed surgery for Medicare beneficiaries. SUMMARY OF BACKGROUND DATA: Lung cancer is the leading cause of cancerrelated death in the United States and rural patients have 20% higher mortality. Drivers of rural disparities along the continuum of lung cancercare delivery are poorly understood. METHODS: Medicare claims (2015-2018) were used to identify 126,352 older adults with an incident diagnosis of nonmetastatic lung cancer. Rural Urban Commuting Area codes were used to define metropolitan, micropolitan, small town, and rural site of residence. Multivariable logistic regression models evaluated influence of place of residence on 1) receipt of cancer-directed surgery, 2) time from diagnosis to surgery, and 3) postoperative outcomes. RESULTS: Metropolitan beneficiaries had higher rate of cancer-directed surgery (22.1%) than micropolitan (18.7%), small town (17.5%), and isolated rural (17.8%) (P < 0.001). Compared to patients from metropolitan areas, there were longer times from diagnosis to surgery for patients living in micropolitan, small, and rural communities. Multivariable models found nonmetropolitan residence to be associated with lower odds of receiving cancer-directed surgery and MIS. Nonmetropolitan residence was associated with higher odds of having postoperative emergency department visits. CONCLUSIONS: Residence in nonmetropolitan areas is associated with lower probability of cancer-directed surgery, increased time to surgery, decreased use of MIS, and increased postoperative ED visits. Attention to timely access to surgery and coordination of postoperative care for nonmetropolitan patients could improve care delivery.

Changes in spending and quality after ACO contract participation for dually eligible beneficiaries with mental illness.

BACKGROUND: Fragmented care and misaligned payment across Medicare and Medicaid lower care quality for dually eligible beneficiaries with mental illness. Accountable care organizations aim to improve the quality and value of care. METHODS: Using Medicare fee-for-service Part A and B claims data from 2009 to 2017 and a difference-in-differences design, we compared the spending and utilization of dually eligible beneficiaries with mental illness that were and were not attributed to Medicare ACO providers before and after ACO contract entry. RESULTS: Dually eligible beneficiaries with mental illness (N = 5,157,533, 70% depression, 22% bipolar, 27% schizophrenia and other psychotic disorders) had average annual Medicare spending of $17,899. ACO contract participation was generally not associated with spending or utilization changes. However, ACO contract participation was associated with higher rates of follow-up visits after mental health hospitalization: 1.17 and 1.30 percentage points within 7 and 30 days of discharge, respectively (p < 0.001). ACO-attributed beneficiaries with schizophrenia, bipolar, or other psychotic disorders received more ambulatory visits (393.9 per 1000 person-years, p = 0.002), while ACO-attributed beneficiaries with depression experienced fewer emergency department visits (-29.5 per 1000 person-years, p = 0.003) after ACO participation. CONCLUSIONS: Dually eligible beneficiaries served by Medicare ACOs did not have lower spending, hospitalizations, or readmissions compared with other beneficiaries. However, ACO participation was associated with timely follow-up after mental health hospitalization, as well as more ambulatory care and fewer ED visits for certain diagnostic groups. IMPLICATIONS: ACOs that include dually eligible beneficiaries with mental illness should tailor their designs to address the distinct needs of this population.

Association of Rurality, Race and Ethnicity, and Socioeconomic Status With the Surgical Management of Colon Cancer and Postoperative Outcomes Among Medicare Beneficiaries.

Importance: Rural patients with colon cancer experience worse outcomes than urban patients, but the extent to which disparities are explained by social determinants is not known. Objectives: To evaluate the association of rurality with surgical treatment and outcomes of colon cancer and to investigate the intersection of rurality with race and ethnicity and socioeconomic status. Design, Settings, and Participants: This cohort study included fee-for-service Medicare beneficiaries 65 years or older diagnosed with incident, nonmetastatic colon cancer between April 1, 2016, and September 30, 2018, with follow-up until December 31, 2018. Data were analyzed from August 3, 2020, to April 30, 2021. Exposures: Rurality of patient's residence, categorized as metropolitan, micropolitan, or small town or rural, using Rural-Urban Commuting Area codes. Main Outcomes and Measures: Receipt of surgery, emergent surgery, or minimally invasive surgery (MIS); 90-day surgical complications; and 90-day mortality. Results: Among 57 710 Medicare beneficiaries with incident, nonmetastatic colon cancer, 46.6% were men, 53.4% were women, and the mean (SD) age was 76.6 (7.2) years. In terms of race and ethnicity, 3.7% were Hispanic, 6.4% were non-Hispanic Black (hereinafter Black), 86.1% were non-Hispanic White (hereinafter White), and 3.8% were American Indian or Alaska Native, Asian or Pacific Islander, or unknown race or ethnicity. Patients residing in nonmetropolitan areas were more likely to undergo surgical resection than those residing in metropolitan areas (69.2% vs 63.9%; P < .001). Black race was independently associated with lower hazard of surgical resection (hazard ratio, 0.92 [95% CI, 0.88-0.95]). Race and ethnicity and measures of socioeconomic status did not modify the association of rurality with surgery. Beneficiaries from small town and rural areas had higher odds of undergoing emergent surgery (adjusted odds ratio [OR], 1.32 [95% CI, 1.20-1.44]) but lower odds of undergoing MIS (adjusted OR, 0.75 [95% CI, 0.70-0.80]), with similar findings for patients residing in micropolitan areas. Members of racial and ethnic minority groups who resided in small town and rural settings experienced higher odds of postoperative surgical complications (P = .001 for interaction) and mortality (P = .001 for interaction). Notably, White patients who resided in small town and rural areas experienced lower odds of postoperative mortality than their White metropolitan counterparts (adjusted OR, 0.81 [95% CI, 0.71-0.92]), but Black patients who resided in small town and rural areas had significantly higher odds of postoperative mortality (adjusted OR, 1.86 [95% CI, 1.16-2.97]) than their Black metropolitan counterparts. Conclusions and Relevance: These findings suggest that Medicare beneficiaries from small town and rural areas were more likely to undergo surgery for nonmetastatic colon cancer than metropolitan beneficiaries but also more likely to undergo emergent surgery and less likely to have MIS. The experiences of rural patients varied by race; rurality was associated with higher postoperative mortality for Black patients but not for other racial and ethnic groups.

Coverage with evidence development: where are we now?

OBJECTIVES: CMS' coverage with evidence development (CED) policy allows Medicare beneficiaries to access promising therapies and services while additional data are collected. CED program characteristics are mostly unreported, and qualities associated with retirement of CED data collection requirements are unknown. We aimed to review and systematically describe CED program history and components and report programmatic elements correlated with retirement of CED data collection requirements, while identifying areas for policy improvement. STUDY DESIGN: Systematic review. METHODS: We extracted CED information from the CMS website, ClinicalTrials.gov, PubMed, internet searches, and communication with CMS. RESULTS: There were 27 CED determinations from 2005 to 2022 in 8 therapeutic areas, with the most for cardiovascular diseases (8/27; 30%). Duration of CED programs (range, 1-16 years) and the number of related registries and clinical trials (range, 0-34) were widely variable. Only 4 CEDs have had data collection requirements with continued National Coverage Determination (NCD); 3 relate to cardiovascular therapies, and all have some public availability of findings resulting from CED-related data collection mechanisms. There were 2 instances of NCD revocation and deferral to local coverage decisions. CONCLUSIONS: Changes in the CED program through improving program predictability and transparency with regard to outstanding questions, roles of relevant stakeholders, and requirements for reporting and reevaluation would strengthen the program's effectiveness. Ultimately, these improvements would provide incentives for stakeholder participation in data collection to achieve the goal of increasing access to beneficial therapies and improving clinical outcomes.

Configuration and Delivery of Primary Care in Rural and Urban Settings.

BACKGROUND: There are concerns about the capacity of rural primary care due to potential workforce shortages and patients with disproportionately more clinical and socioeconomic risks. Little research examines the configuration and delivery of primary care along the spectrum of rurality. OBJECTIVE: Compare structure, capabilities, and payment reform participation of isolated, small town, micropolitan, and metropolitan physician practices, and the characteristics and utilization of their Medicare beneficiaries. DESIGN: Observational study of practices defined using IQVIA OneKey, 2017 Medicare claims, and, for a subset, the National Survey of Healthcare Organizations and Systems (response rate=47%). PARTICIPANTS: A total of 27,716,967 beneficiaries with qualifying visits who were assigned to practices. MAIN MEASURES: We characterized practices' structure, capabilities, and payment reform participation and measured beneficiary utilization by rurality. KEY RESULTS: Rural practices were smaller, more primary care dominant, and system-owned, and had more beneficiaries per practice. Beneficiaries in rural practices were more likely to be from high-poverty areas and disabled. There were few differences in patterns of outpatient utilization and practices' care delivery capabilities. Isolated and micropolitan practices reported less engagement in quality-focused payment programs than metropolitan practices. Beneficiaries cared for in more rural settings received fewer recommended mammograms and had higher overall and condition-specific readmissions. Fewer beneficiaries with diabetes in rural practices had an eye exam. Most isolated rural beneficiaries traveled to more urban communities for care. CONCLUSIONS: While most isolated Medicare beneficiaries traveled to more urban practices for outpatient care, those receiving care in rural practices had similar outpatient and inpatient utilization to urban counterparts except for readmissions and quality metrics that rely on services outside of primary care. Rural practices reported similar care capabilities to urban practices, suggesting that despite differences in workforce and demographics, rural patterns of primary care delivery are comparable to urban.

Low-Value Care at the Actionable Level of Individual Health Systems.

Importance: Low-value health care remains prevalent in the US despite decades of work to measure and reduce such care. Efforts have been only modestly effective in part because the measurement of low-value care has largely been restricted to the national or regional level, limiting actionability. Objectives: To measure and report low-value care use across and within individual health systems and identify system characteristics associated with higher use using Medicare administrative data. Design, Setting, and Participants: This retrospective cohort study of health system-attributed Medicare beneficiaries was conducted among 556 health systems in the Agency for Healthcare Research and Quality Compendium of US Health Systems and included system-attributed beneficiaries who were older than 65 years, continuously enrolled in Medicare Parts A and B for at least 12 months in 2016 or 2017, and eligible for specific low-value services. Statistical analysis was conducted from January 26 to July 15, 2021. Main Outcomes and Measures: Use of 41 individual low-value services and a composite measure of the 28 most common services among system-attributed beneficiaries, standardized to distance from the mean value. Measures were based on the Milliman MedInsight Health Waste Calculator and published claims-based definitions. Results: Across 556 health systems serving a total of 11 637 763 beneficiaries, the mean (SD) use of each of the 41 low-value services ranged from 0% (0.01%) to 28% (4%) of eligible beneficiaries. The most common low-value services were preoperative laboratory testing (mean [SD] rate, 28% [4%] of eligible beneficiaries), prostate-specific antigen testing in men older than 70 years (mean [SD] rate, 27% [8%]), and use of antipsychotic medications in patients with dementia (mean [SD] rate, 24% [8%]). In multivariable analysis, the health system characteristics associated with higher use of low-value care were smaller proportion of primary care physicians (adjusted composite score, 0.15 [95% CI, 0.04-0.26] for systems with less than the median percentage of primary care physicians vs -0.16 [95% CI, -0.27 to -0.05] for those with more than the median percentage of primary care physicians; P < .001), no major teaching hospital (adjusted composite, 0.10 [95% CI, -0.01 to 0.20] without a teaching hospital vs -0.18 [95% CI, -0.34 to -0.02] with a teaching hospital; P = .01), larger proportion of non-White patients (adjusted composite, 0.15 [95% CI, -0.02 to 0.32] for systems with >20% of non-White beneficiaries vs -0.06 [95% CI, -0.16 to 0.03] for systems with ≤20% of non-White beneficiaries; P = .04), headquartered in the South or West (adjusted composite, 0.28 [95% CI, 0.14-0.43] for the South and 0.22 [95% CI, 0.02-0.42] for the West compared with -0.09 [95% CI, -0.26 to 0.08] for the Northeast and -0.44 [95% CI, -0.60 to -0.28] for the Midwest; P < .001), and serving areas with more health care spending (adjusted composite, 0.23 [95% CI, 0.11-0.35] for areas above the median level of spending vs -0.24 [95% CI, -0.36 to -0.12] for areas below the median level of spending; P < .001). Conclusions and Relevance: The findings of this large cohort study suggest that system-level measurement and reporting of specific low-value services is feasible, enables cross-system comparisons, and reveals a broad range of low-value care use.

Imagining a world without low-value services: progress, barriers, and the path forward.

Low-value services are a major problem in the US health care system. We believe that the coronavirus disease 2019 pandemic's unprecedented impact on the health system, and society writ large, offers an opportunity to reshape the conversation and incentives around low-value services. This article explores current barriers to and opportunities for accelerating progress toward high-value care delivery. We examine how financial and nonfinancial incentives, uncertainty in clinical decision-making, and insufficient partnering with patients and families contribute to the delivery of low-value care. We then explore potential solutions, including making it easier for clinicians to forgo low-value services and providing them with actionable information to make those decisions, expanding payer efforts to develop "value report cards," developing measures that map the adverse health and economic effects of low-value services, and training clinicians and health care leaders to engage in conversations with patients about the personal medical, financial, and psychological harms of low-value services.

Estimates of ACO savings in the presence of provider and beneficiary selection.

BACKGROUND: Medicare's accountable care organizations (ACOs)-designed to improve quality and lower spending-were associated with growing savings in previous studies. However, savings estimates may be biased by beneficiary sorting among providers based on healthcare needs and by providers opting into the program based on anticipated gains. METHODS: Using Medicare administrative claims (2009-2014), we compared annual spending changes after provider organizations joined ACOs to changes in non-ACOs (controls). To address provider selection, using novel data to identify non-ACO organizations, we restricted controls to comparably large provider organizations. To address beneficiary selection, we (a) estimated within-organization (including non-ACO comparison organizations) spending changes, (b) estimated within-beneficiary spending changes, (c) incorporated beneficiaries without qualifying healthcare expenses, and (d) used a fixed beneficiary ACO assignment using the pre-ACO period. RESULTS: Each year, 19% of Medicare beneficiaries switched provider organizations. Spending was higher for switchers than stayers ($3163, p < .001) and grew more the next year ($2004; p < .001). Starting from a baseline regression modeled on previous ACO evaluations, estimated savings varied widely as we sequentially introduced methods to address selection. Combining methods, however, generated more stable estimated ACO savings of $46 (p = .022), averaged across cohorts. CONCLUSIONS: When implementing a comprehensive suite of methods to adjust for provider and beneficiary selection, we estimated ACO savings that grew over time. Our estimates are in line with, but smaller than, previous estimates in the literature. Implementing piecemeal adjustments produced misleading results. IMPLICATIONS: Our results confirm the importance of selection for savings estimates and for provider organizations managing costs and quality. Attribution rules that consider multiple years may help mitigate the impact of beneficiary churn for providers and payers. Implementing payment reform by randomizing early participants, or implementing fully across selected markets, may better serve efforts to evaluate and improve payment models. LEVEL OF EVIDENCE: Level 3.

Translating Evidence into Practice: ACOs' Use of Care Plans for Patients with Complex Health Needs.

BACKGROUND: Care plans are an evidence-based strategy, encouraged by the Centers for Medicare and Medicaid Services, and are used to manage the care of patients with complex health needs that have been shown to lead to lower hospital costs and improved patient outcomes. Providers participating in payment reform, such as accountable care organizations, may be more likely to adopt care plans to manage complex patients. OBJECTIVE: To understand how Medicare accountable care organizations (ACOs) use care plans to manage patients with complex clinical needs. DESIGN: A qualitative study using semi-structured interviews with Medicare ACOs. PARTICIPANTS: Thirty-nine interviews were conducted across 18 Medicare ACOs with executive-level leaders and associated clinical and managerial staff. APPROACH: Development, structure, use, and management of care plans for complex patients at Medicare ACOs. KEY RESULTS: Most (11) of the interviewed ACOs reported using care plans to manage care of complex patients. All care plans include information about patient history, current medical needs, and future care plans. Beyond the core elements, care plans included elements based on the ACO's planned use and level of staff and patient engagement with care planning. Most care plans were developed and maintained by care management (not clinical) staff. CONCLUSIONS: ACOs are using care plans for patients with complex needs, but their use of care plans does not always meet the best practices. In many cases, ACO usage of care plans does not align with prescribed best practices: ACOs are adapting use of care plans to better fit the needs of patients and providers.

Assessment of Prevalence and Cost of Care Cascades After Routine Testing During the Medicare Annual Wellness Visit.

Importance: For healthy adults, routine testing during annual check-ups is considered low value and may trigger cascades of medical services of unclear benefit. It is unknown how often routine tests are performed during Medicare annual wellness visits (AWVs) or whether they are associated with cascades of care. Objective: To estimate the prevalence of routine electrocardiograms (ECGs), urinalyses, and thyrotropin tests and of cascades (further tests, procedures, visits, hospitalizations, and new diagnoses) that might follow among healthy adults receiving AWVs. Design, Setting, and Participants: Observational cohort study using fee-for-service Medicare claims data from beneficiaries aged 66 years and older who were continuously enrolled in fee-for-service Medicare between January 1, 2013, and March 31, 2015; received an AWV in 2014; had no test-relevant prior conditions; did not receive 1 of the 3 tests in the 6 months before the AWV; and had no test-relevant symptoms or conditions in the AWV testing period. Data were analyzed from February 13, 2019, to June 8, 2020. Exposure: Receipt of a given test within 1 week before or after the AWV. Main Outcomes and Measures: Prevalence of routine tests during AWVs and cascade-attributable event rates and associated spending in the 90 days following the AWV test period. Patient, clinician, and area-level characteristics associated with receiving routine tests were also assessed. Results: Among 75 275 AWV recipients (mean [SD] age, 72.6 [6.1] years; 48 107 [63.9%] women), 18.6% (14 017) received at least 1 low-value test including an ECG (7.2% [5421]), urinalysis (10.0% [7515]), or thyrotropin test (8.7% [6534]). Patients were more likely to receive a low-value test if they were younger (adjusted odds ratio [aOR], 1.69 for ages 66-74 years vs ages ≥85 years [95% CI, 1.53-1.86]), White (aOR, 1.32 compared with Black [95% CI, 1.16-1.49]), lived in urban areas (aOR, 1.29 vs rural [95% CI, 1.15-1.46]), and lived in high-income areas (aOR, 1.26 for >400% of the federal poverty level vs <200% of the federal poverty level [95% CI, 1.16-1.37]). A total of 6.1 (95% CI, 4.8-7.5) cascade-attributable events per 100 beneficiaries occurred in the 90 days following routine ECGs and 5.4 (95% CI, 4.2-6.5) following urinalyses, with cascade-attributable cost per beneficiary of $9.62 (95% CI, $6.43-$12.80) and $7.46 (95% CI, $5.11-$9.81), respectively. No cascade-attributable events or costs were found to be associated with thyrotropin tests. Conclusions and Relevance: In this study, 19% of healthy Medicare beneficiaries received routine low-value ECGs, urinalyses, or thyrotropin tests during their AWVs, more often those who were younger, White, and lived in urban, high-income areas. ECGs and urinalyses were associated with cascades of modest but notable cost.

Financial Integration's Impact On Care Delivery And Payment Reforms: A Survey Of Hospitals And Physician Practices.

Health systems continue to grow in size. Financial integration-the ownership of hospitals or physician practices-often has anticompetitive effects that contribute to the higher prices for health care seen in the US. To determine whether the potential harms of financial integration are counterbalanced by improvements in quality, we surveyed nationally representative samples of hospitals (n = 739) and physician practices (n = 2,189), stratified according to whether they were independent or were owned by complex systems, simple systems, or medical groups. The surveys included nine scales measuring the level of adoption of diverse, quality-focused care delivery and payment reforms. Scores varied widely across hospitals and practices, but little of this variation was explained by ownership status. Quality scores favored financially integrated systems for four of nine hospital measures and one of nine practice measures, but in no case favored complex systems. Greater financial integration was generally not associated with better quality.

Association between specialist compensation and Accountable Care Organization performance.

OBJECTIVE: To determine if Medicare Shared Savings Program Accountable Care Organizations (ACOs) using cost reduction measures in specialist compensation demonstrated better performance. DATA SOURCES: National, cross-sectional survey data on ACOs (2013-2015) linked to public-use data on ACO performance (2014-2016). STUDY DESIGN: We compared characteristics of ACOs that did and did not report use of cost reduction measures in specialist compensation and determined the association between using this approach and ACO savings, outpatient spending, and specialist visit rates. PRINCIPAL FINDINGS: Of 160 ACOs surveyed, 26 percent reported using cost reduction measures to help determine specialist compensation. ACOs using cost reduction in specialist compensation were more often physician-led (68.3 vs 49.6 percent) and served higher-risk patients (mean Hierarchical Condition Category score 1.09 vs 1.05). These ACOs had similar savings per beneficiary year (adjusted difference $82.6 [95% CI -77.9, 243.1]), outpatient spending per beneficiary year (-24.0 [95% CI -248.9, 200.8]), and specialist visits per 1000 beneficiary years (369.7 [95% CI -9.3, 748.7]). CONCLUSION: Incentivizing specialists on cost reduction was not associated with ACO savings in the short term. Further work is needed to determine the most effective approach to engage specialists in ACO efforts.

Accountable Care Organizations' Increase In Nonphysician Practitioners May Signal Shift For Health Care Workforce.

Both the number and the size of accountable care organizations (ACOs) in the Medicare Shared Savings Program have been increasing. The number of ACOs rose from 220 in 2013 to 548 in 2018, while the average number of participating clinicians in ACOs increased from 263 to 653. Although increases occurred for primary care physicians (from an average of 141 to 251) and medical specialists (from an average of 76 to 157), the increase for nonphysician practitioners (from an average of 47 to 245) was the largest. These differential increases changed the ACO workforce composition over time. The average proportion of nonphysician practitioners in ACOs grew from 18.1 percent to 38.7 percent, with a commensurate decline in the average share of primary care physicians from 60.0 percent to 42.2 percent. As value-based care models grow in prevalence, their evolving clinician composition may affect workforce patterns in the broader health care delivery system.

Accountable care organizations are increasingly led by physician groups rather than hospital systems.

Because hospitals and health systems sponsored the majority of new accountable care organizations (ACOs) from 2010 to 2015, they influenced priorities and strategies of the policies designed to drive ACO adoption. In recent years, however, the majority of new ACOs have been sponsored by physician groups. This shift means that policies need to be developed with the characteristic strengths and weaknesses of physician-led ACOs in mind. Using data from the Leavitt Partners ACO database, we analyzed the types of providers becoming ACOs over time to look at their numbers and market potential. Because the market potential for further growth of physician group-led ACOs is much stronger than for hospital- or health system-led ACOs, policy makers need to create programs and policies that facilitate physician-led ACOs' success by helping them develop the capacity to take on risk, finance investments in high-value healthcare, and partner with other organizations to provide the full spectrum of care.

Association of Organizational Factors and Physician Practices' Participation in Alternative Payment Models.

Importance: Consolidation among physician practices and between hospitals and physician practices has accelerated in the past decade, resulting in higher prices in commercial markets. The resulting integration of health care across clinicians and participation in alternative payment models (APMs), which aim to improve quality while constraining spending, are cited as reasons for consolidation, but little is known about the association between integration and APM participation. Objective: To examine the association of organizational characteristics, ownership, and integration with intensity of participation in APMs among physician practices. Design, Setting, and Participants: A cross-sectional descriptive study, adjusted for sampling and nonresponse weights, was conducted in US physician practice respondents to the National Survey of Healthcare Organizations and Systems conducted between June 16, 2017, and August 17, 2018; of 2333 responses received (response rate, 46.9%) and after exclusion of ineligible and incomplete responses, the number of practices included in the analysis was 2061. Data analysis was performed from April 1, 2019, to August 31, 2019. Exposures: Self-reported physician practice characteristics, including ownership, integration (clinical, cultural, financial, and functional), care delivery capabilities, activities, and environmental factors. Main Outcomes and Measures: Participation in APMs: (1) bundled payments, (2) comprehensive primary care and medical home programs, (3) pay-for-performance programs, (4) capitated contracts with commercial health plans, and (5) accountable care organization contracts. Results: A total of 49.2% of the 2061 practices included reported participating in 3 or more APMs; most participated in pay-for-performance and accountable care organization models. Covariate-adjusted analyses suggested that operating within a health care system (odds ratio [OR] for medical group: 2.35; 95% CI, 1.70-3.25; P < .001; simple health system: 1.46; 95% CI, 1.08-1.97; P = .02; and complex health system: 1.76; 95% CI, 1.25-2.47; P = .001 relative to independent practices), greater clinical (OR, 4.68; 95% CI, 2.28-9.59; P < .001) and functional (OR, 4.24; 95% CI, 2.00-8.97; P < .001) integration, and being located in the Northeast (OR for Midwest: 0.47; 95% CI, 0.34-0.65; P < .001; South: 0.47; 95% CI, 0.34-0.66; P < .001; and West: 0.64; 95% CI, 0.46-0.91; P = .01) were associated with greater APM participation. Conclusions and Relevance: Greater APM participation appears to be supported by integration and system ownership.