Actigraphy methodology in the Kids Mod PAH trial: Physical activity as a functional endpoint in pediatric clinical trials.

Pulmonary vasodilator treatment can improve hemodynamics, right ventricular function, symptoms, and survival in pediatric pulmonary hypertension (PH). However, clinical trial data are lacking due to many constraints. One major limitation is the lack of relevant trial endpoints reflective of hemodynamics or functional status in patients in whom standard exercise testing is impractical, unreliable, or not reproducible. The Kids Mod PAH trial (Mono- vs. Duo Therapy for Pediatric Pulmonary Arterial Hypertension) is an ongoing multicenter, Phase III, randomized, open-label, pragmatic trial to compare the safety and efficacy of first-line combination therapy (sildenafil and bosentan) to first-line monotherapy (sildenafil alone) in 100 pediatric patients with PH across North America. Investigators will measure participants' physical activity with a research-grade, wrist-worn actigraphy device at multiple time points as an exploratory secondary outcome. Vector magnitude counts per minute and activity intensity will be compared between the treatment arms. By directly and noninvasively measuring physical activity in the ambulatory setting, we aim to identify a novel, simple, inexpensive, and highly reproducible approach for quantitative assessment of exercise tolerance in pediatric PH. These data will increase the field's understanding of the effect of pulmonary vasodilator treatment on daily activity - a quantitative measure of functional status and wellbeing in pediatric PH and a potential primary outcome for future clinical trials in children with cardiopulmonary disorders.

Financial Viability of the No Surprises Act Independent Dispute Resolution Process: Radiology and Other Hospital-Based Specialties.

BACKGROUND. The federal No Surprises Act (NSA), designed to eliminate surprise medical billing for out-of-network (OON) care for circumstances beyond patients' control, established the independent dispute resolution (IDR) process to settle clinician-payer payment disputes for OON care. OBJECTIVE. The purpose of our study was to assess the fraction of OON claims for which radiologists and other hospital-based specialists can expect to at least break even when challenging payer-determined payments through the NSA IDR process, as a measure of the process's financial viability. METHODS. This retrospective study extracted claims from a national commercial database (Optum's deidentified Clinformatics Data Mart) for hospital-based specialties occurring on the same day as in-network emergency department (ED) visits or inpatient stays from January 2017 to December 2021. OON claims were identified. OON claims batching was simulated using IDR rules. Maximum potential recovered payments from the IDR process were estimated as the difference between the charges and the allowed amount. The percentages of claims for which the maximum potential payment and one-quarter of this amount (a more realistic payment recovery estimate) would exceed IDR fees were determined, using US$150 and US$450 fee thresholds to approximate the range of final 2024 IDR fees. These values represented the percentage of OON claims that would be financially viable candidates for IDR submission. RESULTS. Among 76,221,264 claims for hospital-based specialties associated with in-network ED visits or inpatient stays, 1,482,973 (1.9%) were OON. The maximum potential payment exceeded fee thresholds of US$150 and US$450 for 55.0% and 32.1%, respectively, of batched OON claims for radiologists and 76.8% and 61.3% of batched OON claims for all other hospital-based specialties combined. At payment of one-quarter of that amount, these values were 26.9% and 10.6%, respectively, for radiologists and 56.6% and 38.4% for all other hospital-based specialties combined. CONCLUSION. The IDR process would be financially unviable for a substantial fraction of OON claims for hospital-based specialists (more so for radiology than for other such specialties). CLINICAL IMPACT. Although the NSA enacted important patient protections, IDR fees limit clinicians' opportunities to dispute payer-determined payments and potentially undermine their bargaining power in contract negotiations. Therefore, IDR rulemaking may negatively impact patient access to in-network care.

The Neiman Imaging Comorbidity Index: Development and Validation in a National Commercial Claims Database.

OBJECTIVE: To build the Neiman Imaging Comorbidity Index (NICI), based on variables available in claims datasets, which provides good discrimination of an individual's chance of receiving advanced imaging (CT, MR, PET), and thus, utility as a control variable in research. METHODS: This retrospective study used national commercial claims data from Optum's deidentified Clinformatics Data Mart database from the period January 1, 2018 to December 31, 2019. Individuals with continuous enrollment during this 2-year study period were included. Lasso (least absolute shrinkage and selection operator) regression was used to predict the chance of receiving advanced imaging in 2019 based on the presence of comorbidities in 2018. A numerical index was created in a development cohort (70% of the total dataset) using weights assigned to each comorbidity, based on regression ß coefficients. Internal validation of assigned scores was performed in the remaining 30% of claims, with comparison to the commonly used Charlson Comorbidity Index. RESULTS: The final sample (development and validation cohorts) included 10,532,734 beneficiaries, of whom 2,116,348 (20.1%) received advanced imaging. After model development, the NICI included nine comorbidities. In the internal validation set, the NICI achieved good discrimination of receipt of advanced imaging with a C statistic of 0.709 (95% confidence interval [CI] 0.708-0.709), which predicted advanced imaging better than the CCI (C 0.692, 95% CI 0.691-0.692). Controlling for age and sex yielded better discrimination (C 0.748, 95% CI 0.748-0.749). DISCUSSION: The NICI is an easily calculated measure of comorbidity burden that can be used to adjust for patients' chances of receiving advanced imaging. Future work should explore external validation of the NICI.

Radiologists' Out-of-Network Billing Trends, 2007 to 2021.

PURPOSE: Given the financial hardships of surprise billing for patients, the aim of this study was to assess the degree to which radiologists effectively participate in commercial insurance networks by examining the trend in the share of radiologists' imaging claims that are out of network (OON). METHODS: A retrospective study over a 15-year period (2007-2021) was conducted using claims from Optum's deidentified Clinformatics Data Mart Database to assess the share of radiologists' imaging claims that are OON. Radiologists' annual OON rate was assessed overall as well as for claims associated with inpatient stays and emergency department (ED) visits. Rates were assessed for all imaging studies as well as by modality. Linear regression was conducted to assess OON rate time trends. RESULTS: From 2007 to 2021, 5,039,142 of radiologists' imaging claims (6.3%) were OON. This rate declined from 12.6% in 2007 to 1.1% in 2021. Over the study period, the OON rate was 5.0% during an inpatient stay and 2.1% on the same day as an ED visit that did not lead to an inpatient admission. The linear trend in the overall OON rate declined 0.74 percentage points annually (95% confidence interval [CI], -0.90 to -0.58 percentage points) over the study period. Likewise, the annual declines were 0.54 percentage points (95% CI, -0.71 to -0.36) and 0.26 percentage points (95% CI, -0.33 to -0.20 percentage points) for imaging claims associated with inpatient stays and ED visits, respectively. CONCLUSIONS: Radiologists' imaging claims that are OON has significantly declined from 2007 to a minimal level in 2021. This may indicate effective negotiations between radiologists and commercial payers and new state-level surprise billing laws.

Ultrasound Utilization Among Medicare Beneficiaries From 2009 to 2021 by Billing Specialty and Place of Service.

Patterns of ultrasound utilization in the national Medicare population shifted from 2009 to 2021. Office ultrasound services were increasingly performed by radiologists, whereas hospital outpatient and inpatient services were increasingly performed by cardiologists/cardiac surgeons; ultrasound services in other places of service were increasingly performed by nonphysician practitioners.

Sociodemographic Factors and Screening CT Colonography Use Among Medicare Beneficiaries.

BACKGROUND. Approximately one-third of the eligible U.S. population have not undergone guideline-compliant colorectal cancer (CRC) screening. Guidelines recognize various screening strategies to increase adherence. CMS provides coverage for all recommended screening tests except CT colonography (CTC). OBJECTIVE. The purpose of this study was to compare CTC and other CRC screening tests in terms of associations of utilization with income, race and ethnicity, and urbanicity in Medicare fee-for-service beneficiaries. METHODS. This retrospective study used CMS Research Identifiable Files from January 1, 2011, through December 31, 2020. These files contain claims information for 5% of Medicare fee-for-service beneficiaries. Data were extracted for individuals 45-85 years old, and individuals with high CRC risk were excluded. Multivariable logistic regression models were constructed to determine the likelihood of undergoing CRC screening tests (as well as of undergoing diagnostic CTC, a CMS-covered test with similar physical access as screening CTC) as a function of income, race and ethnicity, and urbanicity while controlling for sex, age, Charlson comorbidity index, U.S. census region, screening year, and related conditions and procedures. RESULTS. For 12,273,363 beneficiary years (mean age, 70.5 ± 8.2 [SD] years; 2,436,849 unique beneficiaries: 6,774,837 female beneficiaries, 5,498,526 male beneficiaries), there were 785,103 CRC screenings events, including 645 for screening CTC. Compared with individuals living in communities with per capita income of less than US$25,000, individuals in communities with income of US$100,000 or more had OR for undergoing screening CTC of 5.73, optical colonoscopy (OC) of 1.36, sigmoidoscopy of 1.03, guaiac fecal occult blood test or fecal immunochemical test of 1.50, stool DNA of 1.43, and diagnostic CTC of 2.00. The OR for undergoing screening CTC was 1.00 for Hispanic individuals and 1.08 for non-Hispanic Black individuals compared with non-Hispanic White individuals. Compared with the OR for undergoing screening CTC for residents of metropolitan areas, the OR was 0.51 for residents of micropolitan areas and 0.65 for residents of small or rural areas. CONCLUSION. The association with income was substantially larger for screening CTC than for other CRC screening tests or for diagnostic CTC. CLINICAL IMPACT. Medicare's noncoverage for screening CTC may contribute to lower adherence with CRC screening guidelines for lower-income beneficiaries. Medicare coverage of CTC could reduce income-based disparities for individuals avoiding OC owing to invasiveness, need for anesthesia, or complication risk.

An exercise stress test for contrast-enhanced duplex ultrasound assessment of lower limb muscle perfusion in patients with peripheral arterial disease.

OBJECTIVE: The aim of the present study was to develop a standardized contrast-enhanced duplex ultrasound (CE-DUS) protocol to assess lower-extremity muscle perfusion before and after exercise and determine relationships of perfusion with clinical and functional measures. METHODS: CE-DUS (EPIQ 5G, Philips) was used before and immediately after a 10-minute, standardized bout of treadmill walking to compare microvascular perfusion of the gastrocnemius muscle in older (55-82 years) patients with peripheral arterial disease (PAD) (n = 15, mean ankle-brachial index, 0.78 ± 0.04) and controls (n = 13). Microvascular blood volume (MBV) and microvascular flow velocity (MFV) were measured at rest and immediately following treadmill exercise, and the Modified Physical Performance Test (MPPT) was used to assess mobility function. RESULTS: In the resting state (pre-exercise), MBV in patients with PAD was not significantly different than normal controls (5.17 ± 0.71 vs 6.20 ± 0.83 arbitrary units (AU) respectively; P = .36); however, after exercise, MBV was ∼40% lower in patients with PAD compared with normal controls (5.85 ± 1.13 vs 9.53 ± 1.31 AU, respectively; P = .04). Conversely, MFV was ∼60% higher in patients with PAD compared with normal controls after exercise (0.180 ± 0.016 vs 0.113 ± 0.018 AU, respectively; P = .01). There was a significant between-group difference in the exercise-induced changes in both MBV and MFV (P ≤ .05). Both basal and exercise MBV directly correlated with MPPT score in the patients with PAD (r = 0.56-0.62; P < .05). CONCLUSIONS: This standardized protocol for exercise stress testing of the lower extremities quantifies calf muscle perfusion and elicits perfusion deficits in patients with PAD. This technique objectively quantifies microvascular perfusion deficits that are related to reduced mobility function and could be used to assess therapeutic efficacy in patients with PAD.

Projected Growth in FDA-Approved Artificial Intelligence Products Given Venture Capital Funding.

PURPOSE: Medical imaging accounts for 85% of digital health's venture capital funding. As funding grows, it is expected that artificial intelligence (AI) products will increase commensurately. The study's objective is to project the number of new AI products given the statistical association between historical funding and FDA-approved AI products. METHODS: The study used data from the ACR Data Science Institute and for the number of FDA-approved AI products (2008-2022) and data from Rock Health for AI funding (2013-2022). Employing a 6-year lag between funding and product approved, we used linear regression to estimate the association between new products approved in a certain year, based on the lagged funding (ie, product-year funding). Using this statistical relationship, we forecasted the number of new FDA-approved products. RESULTS: The results show that there are 11.33 (95% confidence interval: 7.03-15.64) new AI products for every $1 billion in funding assuming a 6-year lag between funding and product approval. In 2022 there were 69 new FDA-approved products associated with $4.8 billion in funding. In 2035, product-year funding is projected to reach $30.8 billion, resulting in 350 new products that year. CONCLUSIONS: FDA-approved AI products are expected to grow from 69 in 2022 to 350 in 2035 given the expected funding growth in the coming years. AI is likely to change the practice of diagnostic radiology as new products are developed and integrated into practice. As more AI products are integrated, it may incentivize increased investment for future AI products.

Prevalence of "One-Off Events" in Radiology: Implications for Radiology in Episode-Based Alternative Payment Models.

OBJECTIVE: As reimbursement mechanisms become more value-based, there are questions about the applicability of these mechanisms for nonepisodic care, particularly care provided by nonpatient-facing specialists, for example, radiologists. Accordingly, this study examined the prevalence of nonepisodic care-one-off events-in diagnostic radiology. METHODS: We conducted a multiyear (2015-2019) retrospective study of diagnostic imaging using a large commercial payer database including commercial insurance and Medicare Advantage. Using a 12-month evaluation period starting with the day of the initial imaging study/studies, we categorized imaging studies as one-off events if there were no additional studies (beyond the first day of the evaluation period) for the next 12 months in the same body region. We also evaluated an alternative, more stringent definition of a one-off event: the only imaging study during the 12-month evaluation period. We computed the percentage of one-off events overall and by body region. RESULTS: We found that one-off events comprised 33.2%-45.8% of imaging studies depending on whether one-off events are defined as the only study in the evaluation period or imaging only on the first day of the evaluation period, respectively. This share varied widely by body region: highest for cardiac (80.9%-87.7%) and lower for chest (26.8%-35.2%). By place-of-service, the proportion was lowest for the inpatient (12.9%-29.1%) and long-term care settings (18.6%-30%). DISCUSSION: Given the sizeable share of imaging studies categorized as one-off events, much of radiologists' workload falls outside of the framework of episodic measurement tools and value-based payment models.

Dual-energy X-ray Absorptiometry Trends Among US Medicare Beneficiaries: 2005-2019.

INTRODUCTION: Bone density measured using dual-energy X-ray absorptiometry (DXA) volume, performance site and interpreters have changed in the US since 2005. The purpose of this report is to provide updated trends in DXA counts, rates, place of service and interpreter specialty for the Medicare fee-for-service population. METHODS: The 100 % Medicare Physician/Supplier Procedure Summary Limited Data Set between 2005-2019 was used. DXA counts and annual rates per 10,000 Medicare beneficiaries were calculated. Annual distributions of scan performance location, provider type and interpreter specialty were described. Place of service trends (significance assigned at p < 0.05) of the mean annual share of DXA utilization were identified using linear regression. RESULTS: Annual DXA use per 10,000 beneficiaries peaked in 2008 at 832, declined to 656 in 2015 then increased (p < 0.001) by 38 per year to 807 in 2019. From 2005 to 2019 DXA performance in office settings declined from 70.7 % to 47.2 %. Concurrently, outpatient hospital (OH) DXA increased from 28.6 % to 51.7 %. In 2005, 43.5 % of DXAs were interpreted by radiologists. This increased (p < 0.001) in the office and OH, averaging 0.3 and 2.0 percentage points per year respectively, reaching 73.5 % in 2019. Interpretation by most non-radiologist specialties declined (p < 0.001). CONCLUSIONS: From 2005-2019, total DXA use among Medicare beneficiaries declined reaching a nadir in 2015 then returned to 2005 levels by 2019. Office DXA declined since 2005 with 51.7 % of all scans now occurring in an OH setting. The proportion of DXAs interpreted by radiologists increased over time, reaching 73.5 % in 2019.

Kids Mod PAH trial: A multicenter trial comparing mono- versus duo-therapy for initial treatment of pediatric pulmonary hypertension.

Pulmonary hypertension (PH) is a significant health problem that contributes to high morbidity and mortality in diverse cardiac, pulmonary, and systemic diseases in children. Evidence-based advances in PH care have been challenged by a paucity of quality endpoints for assessing clinical course and the lack of robust clinical trial data to guide pharmacologic therapies in children. While the landmark adult AMBITION trial demonstrated the benefit of up-front combination PH therapy with ambrisentan and tadalafil, it remains unknown whether upfront combination therapy leads to more rapid and sustained clinical benefits in children with various categories of PH. In this article, we describe the inception of the Kids Mod PAH Trial, a multicenter Phase III trial, to address whether upfront combination therapy (sildenafil and bosentan vs. sildenafil alone) improves PH outcomes in children, recognizing that marked differences between the etiology and therapeutic response between adults and children exist. The primary endpoint of this study is WHO functional class (FC) 12 months after initiation of study drug therapy. In addition to the primary outcome, secondary endpoints are being assessed, including a composite measure of time to clinical worsening, WHO FC at 24 months, echocardiographic assessment of PH and quantitative assessment of right ventricular function, 6-min walk distance, and NT-proBNP levels. Exploratory endpoints include selected biomarkers, actigraphy, and assessments of quality of life. This study is designed to pave the way for additional clinical trials by establishing a robust infrastructure through the development of a PPHNet Clinical Trials Network.

Budget Neutrality and Medicare Physician Fee Schedule Reimbursement Trends for Radiologists, 2005 to 2021.

PURPOSE: The Medicare program, by law, must remain budget neutral. Increases in volume or relative value units (RVUs) for individual services necessitate declines in either the conversion factor or assigned RVUs for other services for budget neutrality. This study aimed to assess the contribution of budget neutrality on reimbursement trends per Medicare fee-for-service beneficiary for services provided by radiologists. METHODS: The study used aggregated 100% of Medicare Part B claims from 2005 to 2021. We computed the percentage change in reimbursement per beneficiary, actual and inflation adjusted, to radiologists. These trends were then adjusted by separately holding constant RVUs per beneficiary and the conversion factor to demonstrate the impact of budget neutrality. RESULTS: Unadjusted reimbursement to radiologists per beneficiary increased 4.2% between 2005 and 2021, but when adjusted for inflation, it declined 24.9%. Over this period, the conversion factor declined 7.9%. Without this decline, the reimbursement per beneficiary would have been 9 percentage points higher in 2021 compared with actual. RVUs per beneficiary performed by radiologists increased 13.1%. Keeping RVUs per beneficiary at 2005 levels, reimbursement per beneficiary would have been 12.1 percentage points lower than observed in 2021. CONCLUSIONS: Given budget neutrality, a substantial decline has occurred in inflation-adjusted reimbursement to radiologists per Medicare beneficiary. Decreases due to both inflation and the decline in conversion factor are only partially offset by increased RVUs per beneficiary, meaning more services per patient with less overall pay, an equation likely to heighten access challenges for Medicare beneficiaries and shortages of radiologists.

Trends in Diagnostic Imaging by Nonphysician Practitioners and Associations With Urbanicity and Scope-of-Practice Authority.

OBJECTIVE: We aimed to assess the changing share of diagnostic imaging billed by NPPs and how such changes differ by urbanicity within the context of scope-of-practice (SOP) regulations and legislation. METHODS: This retrospective cohort study used patient claims for diagnostic imaging studies spanning 2016-2020 from Optum Clinformatics Datamart datasets. Multivariable modeling determined the odds of patients receiving NPP-interpreted vs physician-interpreted imaging. Imaging rates and trends in proportions of NPP-billed claims were assessed by urbanicity and relative to other factors including SOP, imaging modality, and place of service. RESULTS: Of all identified imaging claims, 3,348,881 (3.0%) were attributed to NPPs, with the highest rates of NPP interpretations per 10,000 images occurring in rural and small-town areas. From 2016 to 2020, the rate of NPP-billed imaging increased from 257 to 331 claims per 10,000 beneficiaries (P = 0.004), observed across both metropolitan (240 to 315, P = 0.001) and micropolitan (367 to 436, P = 0.020) settings. Although rates in rural and small-town areas rose, the increase was not significant (330 to 392, P = 0.363). Rises in NPP imaging in metropolitan settings occurred in states with moderately restrictive (307 to 358, P = 0.008) and least restrictive (289 to 419, P = 0.004) SOP legislation. DISCUSSION: Rates of diagnostic imaging interpretation by NPPs are rising. Growth in recent years appears driven by metropolitan areas in states with less restrictive SOP regulations. Future work is necessary to assess the quality of and downstream costs related to increasing NPP-interpreted imaging.

Imaging Utilization Patterns in the Follow-Up of Extremity Soft Tissue Sarcomas in the United States.

This study aimed to describe patterns of imaging utilization after resection of extremity soft tissue sarcoma in the United States, assess for potential disparities, and evaluate temporal trends. A retrospective cohort study using a national database of private payer claims data was performed to determine the utilization rate of extremity and chest imaging in a 5-year postoperative follow-up period for patients with extremity soft tissue sarcoma treated between 2007 and 2019. Imaging utilization was assessed according to patient demographics (age, sex, race and ethnicity, and region of residency), calendar year of surgery, and postoperative year. Associations of demographic variables with imaging use were assessed using chi-square tests, trends in imaging use were analyzed using the Cochran-Armitage trend test or linear regression, and associations of postoperative year with imaging use were evaluated with the Pearson Correlation coefficient. A total of 3707 patients were included. Most patients received at least 1 chest (74%) and extremity (53%) imaging examination during their follow-up period. The presence of surveillance imaging was significantly associated with age (P < 0.0001) and region (P = 0.0029). Over the study period, there was an increase in use of extremity MRI (P < 0.05) and ultrasound (P < 0.01) and chest CT (P < 0.0001) and a decrease in use of chest radiographs (P < 0.0001). Imaging use declined over postoperative years (decrease by 85%-92% from year 1-5). In conclusion, the use of surveillance imaging varied according to patient demographics and has increased for extremity MRI and ultrasound and chest CT over the study period.

Urbanicity, Income, and Mammography-Use Disparities Among American Indian Women.

INTRODUCTION: Reported breast cancer screening among American Indian women is consistently below that of White women. The last claims-based trends were from 1991 to 2001. This study updates mammography trends for American Indian women and examines the impact of race, urbanicity, and income on long-term mammography use. METHODS: This was a multi-year (2005-2019), retrospective study of women aged 40-89 years using a 5% sample of Medicare fee-for-service beneficiaries residing in Arizona, California, New Mexico, Oklahoma, and Washington. This study used multivariable logistic regression to examine the impact of urbanicity and income on receiving mammography for American Indian women compared with that for White women. Analyses were conducted in 2022. RESULTS: Overall, annual age-adjusted mammography use declined from 205 per 1,000 in 2005 to 165 per 1,000 in 2019. The slope of these declines was significantly steeper (difference = -2.41, p<0.001) for White women (-3.06) than for American Indian women (-0.65). Mammography-use odds across all urbanicity categories were less for American Indian women than for White women compared with those of their respective metropolitan counterparts (e.g., rural: 0.96, 95% CI=0.77, 1.20 for American Indian women and 1.47, 99% CI=1.39, 1.57 for White women). Although residing in higher-income communities was not associated with mammography use for American Indian women, it was 31% higher for White women (OR=1.31, 99% CI=1.28, 1.34). CONCLUSIONS: The disparity in annual age-adjusted mammography use between American Indian and White women narrowed between 2005 and 2019. However, the association of urbanicity and community income on mammography use differs substantially between American Indian and White women. Policies to reduce disparities need to consider these differences.

Relationship between Race and Access to Newer Mammographic Technology in Women with Medicare Insurance.

Background Racial disparities in breast cancer mortality have been reported. Mammographic technology has undergone two major technology transitions since 2000: first, the transition from screen-film mammography (SFM) to full-field digital mammography (FFDM) and second, the transition to digital breast tomosynthesis (DBT). Purpose To examine the relationship between use of newer mammographic technology and race in women receiving mammography services. Materials and Methods This was a multiyear (January 2005 to December 2020) retrospective study of women aged 40-89 years with Medicare fee-for-service insurance who underwent mammography. Data were obtained using a 5% research identifiable sample of all Medicare fee-for-service beneficiaries. Within-institution and comparable-institution use of mammographic technology between Black women or women of other races and White women were assessed with multivariable logistic and linear regression, respectively, adjusted for age, race, Charlson comorbidity index, per capita income, urbanicity, and institutional capability. Results Between 2005 and 2020, there were 4 028 696 institutional mammography claims for women (mean age, 72 years ± 8 [SD]). Within an institution, the odds ratio (OR) of Black women receiving digital mammography rather than SFM in 2005 was 0.80 (95% CI: 0.70, 0.91; P < .001) when compared with White women; these differences remained until 2009. Compared with White women, the use of DBT within an institution was less likely for Black women from 2015 to 2020 (OR, 0.84; 95% CI: 0.81, 0.87; P < .001). Across institutions, there were racial differences in digital mammography use, which followed a U-shaped pattern, and the differences peaked at 3.8 percentage points less for Black compared with White women (95% CI: -6.1, -1.6; P = .001) in 2011 and then decreased to 1.2 percentage points less (95% CI: -2.2, -0.2; P = .02) in 2016. Conclusion In the Medicare population, Black women had less access to new mammographic imaging technology compared with White women for both the transition from screen-film mammography to digital mammography and then for the transition to digital breast tomosynthesis. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Lee and Lawson in this issue.

Drivers of Ischemic Stroke Hospital Cost Trends Among Older Adults in the United States.

PURPOSE: The increased use of neuroimaging and innovations in ischemic stroke (IS) treatment have improved outcomes, but the impact on median hospital costs is not well understood. METHODS: A retrospective study was conducted using Medicare 5% claims data for 75,525 consecutive index IS hospitalizations for patients aged ≥65 years from 2012 to 2019 (values in 2019 dollars). IS episode cost was calculated in each year for trend analysis and stratified by cost components, including neuroimaging (CT angiography [CTA], CT perfusion [CTP], MRI, and MR angiography [MRA]), treatment (endovascular thrombectomy [EVT] and/or intravenous thrombolysis), and patient sociodemographic factors. Logistic regression was performed to analyze the drivers of high-cost episodes and median regression to assess drivers of median costs. RESULTS: The median IS episode cost increased by 4.9% from $9,509 in 2012 to $9,973 in 2019 (P = .0021). Treatment with EVT resulted in the greatest odds of having a high-cost (>$20,000) hospitalization (odds ratio [OR], 71.86; 95% confidence interval [CI], 54.62-94.55), as did intravenous thrombolysis treatment (OR, 3.19; 95% CI, 2.90-3.52). Controlling for other factors, neuroimaging with CTA (OR, 1.72; 95% CI, 1.58-1.87), CTP (OR, 1.32; 95% CI, 1.14-1.52), and/or MRA (OR, 1.26; 95% CI, 1.15-1.38) had greater odds of having high-cost episodes than those without CTA, CTP, and MRA. Length of stay > 4 days (OR, 4.34; 95% CI, 3.99-4.72) and in-hospital mortality (OR, 1.85; 95% CI, 1.63-2.10) were also associated with high-cost episodes. CONCLUSIONS: From 2012 to 2019, the median IS episode cost increased by 4.9%, with EVT as the main cost driver. However, the increasing treatment cost trends have been partially offset by decreases in median length of stay and in-hospital mortality.

Association of State Share of Nonphysician Practitioners With Diagnostic Imaging Ordering Among Emergency Department Visits for Medicare Beneficiaries.

Importance: The use of nonphysician practitioners (NPPs) in the emergency department (ED) continues to expand, yet little is known about associations between NPPs and ED imaging use. Objective: To investigate whether the state share of ED visits for which an NPP was the clinician of record is associated with imaging studies ordered, given that state NPP share is associated with state-level NPP scopes of practice. Design, Setting, and Participants: This cross-sectional study compared diagnostic imaging ordering patterns associated with ED visits based on 2005-2020 Medicare claims for a nationally representative 5% sample of fee-for-service beneficiaries. For all 50 states and the District of Columbia, the state NPP share of ED visits by year was used to represent state-specific practice patterns for NPPs and physicians and how those patterns have evolved over time. The analysis controlled for patient demographic characteristics, Charlson Comorbidity Index scores, ED visit severity, year, and principal diagnosis. Exposures: The share of ED visits in each state in each year (state share) for which an NPP was the evaluation and management clinician. Main Outcomes and Measures: The main outcomes were the number and modality of imaging studies associated with ED visits. Analyses were by logistic regression and generalized linear model with γ-distribution and log-link function. Results: Among 16 922 274 ED visits, 60.0% involved women, and patients' mean (SD) age was 70.3 (16.1) years. The share of all ED visits with an NPP as the clinician increased from 6.1% in 2005 to 16.6% in 2020. Compared with no NPPs, the presence of NPPs in the ED was associated with 5.3% (95% CI, 5.1%-5.5%) more imaging studies per ED visit, including a 3.4% (95% CI, 3.2%-3.5%) greater likelihood of any imaging order per ED visit and 2.2% (95% CI, 2.0%-2.3%) more imaging studies ordered per visit involving imaging. Conclusions and Relevance: In this study, use of NPPs in the ED was associated with higher imaging use compared with the use of only physicians in the ED. Although expanded use of NPPs in the ED may improve patient access, the costs and radiation exposure associated with more imaging warrants additional study.