USACS Research Group

Guiding Principles

• Dedication to our Mission. We prioritize research in clinical care, systems-based processes, population health, health services, and resource utilization. 
• Publication Commitment. We are committed to publication in peer-reviewed literature regardless of the results to ensure the integrity of our research process. 
• Internal Collaboration. We offer research opportunities to our fellow USACS partners. 
• External Collaboration. We partner with external experts. We consider participation in externally led research that aligns with our mission, vision, and principles. To date, we have active collaborations with Brown University, George Washington University, Northwestern, Georgetown, Yale, University of Pittsburgh, and University of Michigan.
• External Funding. We seek funding to support our research mission, vision, and principles. Funders shall not influence our results or commitment to publishing. 
• Regulatory and ethical norms. We conform to all regulatory and ethical requirements of research, clinical care, and USACS. 

As a practice dedicated to academics, we are proud to share the scholarly activity of our colleagues who are making an impact on their specialties.

What We Publish

See some of the important questions the USACS Research Group has answered.

Q: How have emergency department (ED) visit volumes, illness severity, and crowding metrics changed from the start of the COVID-19 pandemic through mid-2022 among 14 million visits?

A: Although total ED visit volumes fell early in the pandemic and remained below 2019 levels through 2022, the proportion of high-acuity and critical care visits increased. Paradoxically, ED crowding and length of stay worsened during this period, particularly for psychiatric patients.

Oskvarek JJ, Zocchi MS, Black BS, Celedon P, Leubitz A, Moghtaderi A, Nikolla DA, Rahman N, Pines JM; US Acute Care Solutions Research Group. Emergency Department Volume, Severity, and Crowding Since the Onset of the Coronavirus Disease 2019 Pandemic. Ann Emerg Med. 2023 Dec;82(6):650-660. doi: 10.1016/j.annemergmed.2023.07.024. Epub 2023 Aug 30. PMID: 37656108.

https://www.sciencedirect.com/science/article/abs/pii/S019606442300598X

Q: What is the effect of a direct, personalized peer-comparison feedback program on the opioid prescribing rates across 5.3 million ED discharges?

A: Direct feedback and an electronic peer-comparison dashboard resulted in a 19% relative reduction in opioid prescribing. The impact was most pronounced among the highest-prescribing Clinicians, who saw reductions between 35% and 41%.

Oskvarek JJ, Aldeen A, Shawbell J, Venkat A, Zocchi MS, Pines JM; US Acute Care Solutions Research Group. Opioid Prescription Reduction After Implementation of a Feedback Program in a National Emergency Department Group. Ann Emerg Med. 2022 May;79(5):420-432. doi: 10.1016/j.annemergmed.2021.12.009. Epub 2022 Jan 25. PMID: 35086726.

https://www.annemergmed.com/article/S0196-0644(21)01528-6/fulltext 

Q: How did the decline in pediatric ED visits during the COVID-19 pandemic compare to adult visit declines across 2.2 million visits?

A: Pediatric ED visits fell much more sharply than adult visits, reaching a peak decline of 74% for young children by April 2020. Even for serious conditions like appendicitis, pediatric visits remained significantly depressed through the summer of 2020.

Pines JM, Zocchi MS, Black BS, Carlson JN, Celedon P, Moghtaderi A, Venkat A; US Acute Care Solutions Research Group. Characterizing pediatric emergency department visits during the COVID-19 pandemic. Am J Emerg Med. 2021 Mar;41:201-204. doi: 10.1016/j.ajem.2020.11.037. Epub 2020 Nov 23. PMID: 33257144; PMCID: PMC7682424.

https://pmc.ncbi.nlm.nih.gov/articles/PMC7682424/ 

Q: Do clinical efficiency and practice patterns differ between new graduates of 3-year vs. 4-year residency programs across 1 million ED encounters?

A: There were no significant differences in efficiency, safety, or flow metrics between graduates of the two training lengths during their first year of practice. Both groups performed similarly to experienced hires, though new graduates were more conservative in prescribing opioids.

Nikolla DA, Zocchi MS, Pines JM, Kaji AH, Venkat A, Beeson MS, Carlson JN. Four- and three-year emergency medicine residency graduates perform similarly in their first year of practice compared to experienced physicians. Am J Emerg Med. 2023 Jul;69:100-107. doi: 10.1016/j.ajem.2023.04.017. Epub 2023 Apr 15. PMID: 37086654.

https://www.sciencedirect.com/science/article/abs/pii/S073567572300205X 

Q: What is the financial relationship between revenue and costs for different payer types in U.S. EDs from 2016 to 2019?

A: Among 576.5 million ED visits, Emergency Clinician services rely on a massive cross-subsidy where high revenue from commercially insured patients offsets significant losses from Medicare, Medicaid, and uninsured patients. The study estimates $2.7 billion in annual foregone revenue for treating the uninsured.

Pines JM, Zocchi MS, Black BS, Carr BG, Celedon P, Janke AT, Moghtaderi A, Oskvarek JJ, Venkatesh AK, Venkat A; US Acute Care Solutions Research Group. The Cost Shifting Economics of United States Emergency Department Professional Services (2016-2019). Ann Emerg Med. 2023 Dec;82(6):637-646. doi: 10.1016/j.annemergmed.2023.04.026. Epub 2023 Jun 17. PMID: 37330720.

https://www.sciencedirect.com/science/article/abs/pii/S0196064423003530 

Q: Does the rising acuity and complexity of patients affect throughput enough to alter Clinician scheduling, or are temporal and facility factors more important?

A: Patient acuity, complexity, and critical procedures have relatively little impact on overall ED throughput. Instead, temporal factors (time of day and day of week) are far more critical for effectively scheduling Clinicians.

Pines JM, Zocchi MS, De Maio VJ, Carlson JN, Bedolla J, Venkat A; US Acute Care Solutions Research Group. The Effect of Operational Stressors on Emergency Department Clinician Scheduling and Patient Throughput. Ann Emerg Med. 2020 Nov;76(5):646-658. doi: 10.1016/j.annemergmed.2020.02.005. Epub 2020 Apr 21. PMID: 32331842.

https://www.annemergmed.com/article/S0196-0644(20)30102-5/fulltext 

Q: How does the scheduling of APPs affect ED productivity, flow, safety, and patient experience?

A: The use of APPs had a marginal impact on ED productivity and flow, with no identified economies of scale relative to Physicians. Furthermore, no significant impact on patient safety or experience was identified.

Pines JM, Zocchi MS, Ritsema T, Polansky M, Bedolla J, Venkat A; US Acute Care Solutions Research Group. The Impact of Advanced Practice Provider Staffing on Emergency Department Care: Productivity, Flow, Safety, and Experience. Acad Emerg Med. 2020 Nov;27(11):1089-1099. doi: 10.1111/acem.14077. Epub 2020 Jul 31. PMID: 32638486.

https://onlinelibrary.wiley.com/doi/10.1111/acem.14077 

Q: What factors—practice-level, clinical, or jurisdictional—are most associated with a Physician being named in a malpractice claim?

A: After adjusting for multiple variables, the only factors significantly associated with being named in a malpractice claim were the total volume of patient visits seen and the total years worked.

Carlson JN, Foster KM, Pines JM, Corbit CK, Ward MJ, Hydari MZ, Venkat A. Provider and Practice Factors Associated With Emergency Physicians' Being Named in a Malpractice Claim. Ann Emerg Med. 2018 Feb;71(2):157-164.e4. doi: 10.1016/j.annemergmed.2017.06.023. Epub 2017 Jul 26. PMID: 28754358; PMCID: PMC5785561. 

https://pmc.ncbi.nlm.nih.gov/articles/PMC5785561/ 

Q: What are the causes, effects, and potential solutions to ED crowding, particularly in the context of the COVID-19 pandemic?

A: ED crowding is driven by input, throughput, and output factors like high patient volumes and boarding, leading to increased mortality and treatment delays. Effective solutions include provider-in-triage and split-flow models, though high-quality evidence remains limited.

Oskvarek JJ, Leubitz A, Rahman N, Sure B, Pines JM. Emergency Department Crowding in the Modern Era: A Systematic Review (2018-2025). Clin Exp Emerg Med. 2026 Jan 14. doi: 10.15441/ceem.25.172. Epub ahead of print. PMID: 41554283.

https://www.ceemjournal.org/journal/view.php?doi=10.15441/ceem.25.172 

Q: How reliable is patient experience survey data (e.g., Press Ganey) when evaluated at the individual Physician and site levels?

A: Patient experience data varies greatly from month to month at both the Physician and facility levels. The variability of patient experience data is markedly higher at the Physician level than at the facility level. Construct validity is greater for facility-level scores than Physician-level scores.

Pines JM, Penninti P, Alfaraj S, Carlson JN, Colfer O, Corbit CK, Venkat A. Measurement Under the Microscope: High Variability and Limited Construct Validity in Emergency Department Patient-Experience Scores. Ann Emerg Med. 2018 May;71(5):545-554.e6. doi: 10.1016/j.annemergmed.2017.11.011. Epub 2017 Dec 18. PMID: 29269006.

https://www.sciencedirect.com/science/article/abs/pii/S0196064417318991 

Q: How frequently do Emergency Physicians perform intubations in actual clinical practice across different settings?

A: In general ED practice, Physicians perform a median of 10 intubations annually. This frequency drops significantly in pediatric EDs, freestanding EDs, and urgent care centers.

Carlson JN, Zocchi M, Marsh K, McCoy C, Pines JM, Christensen A, Kornas R, Venkat A. Procedural Experience With Intubation: Results From a National Emergency Medicine Group. Ann Emerg Med. 2019 Dec;74(6):786-794. doi: 10.1016/j.annemergmed.2019.04.025. Epub 2019 Jun 24. PMID: 31248674.

https://www.sciencedirect.com/science/article/abs/pii/S0196064419303488 

Q: Is a specific admission intensity measure stable across hundreds of EDs for use in value-based care programs?

A: The measure demonstrated high stability for characterizing facility-level admission rates across 358 EDs and reliably identified individual Physicians who were consistently high or low admitters relative to peers.

Janke AT, Oskvarek JJ, Zocchi MS, Cai AG, Litvak O, Pines JM, Venkatesh AK. Reliability of a Measure of Admission Intensity for Emergency Physicians. Ann Emerg Med. 2024 Sep;84(3):295-304. doi: 10.1016/j.annemergmed.2024.02.002. Epub 2024 Mar 2. PMID: 38430082.

https://www.sciencedirect.com/science/article/abs/pii/S0196064424000829 

Q: What Physician- and shift-level factors are associated with clinical productivity across over 200k shifts?

A: Productivity increases with younger Physician age and longer site tenure, but is negatively impacted by overnight shifts and high boarding periods. Higher productivity was associated with slightly lower 72-hour return rates.

Oskvarek JJ, Zocchi MS, Black BS, Burke LG, Kachman M, Leubitz A, Moghtaderi A, Nikolla DA, Rahman N, Pines JM. Predictors of Emergency Physician Productivity in a National Emergency Medicine Group. Ann Emerg Med. 2025 Oct;86(4):347-358. doi: 10.1016/j.annemergmed.2025.02.002. Epub 2025 Mar 28. PMID: 40152844.

https://www.sciencedirect.com/science/article/abs/pii/S0196064425000630 

Q: How do Locum Tenens and employed Travel Physicians compare to permanent staff regarding clinical productivity and other measures of practice?

A: Locum Tenens Physicians were modestly less productive than permanent staff during their first 100 shifts. However, other care measures, such as return visits and imaging utilization, were similar across all Physician types.

Nikolla DA, Zocchi MS, Black BS, Oskvarek JJ, Burke LG, Kachman MM, Moghtaderi A, Rahman N, Bedolla J, Carlson JN, Pines JM; US Acute Care Solutions Research Group. Differences in Productivity and Clinical Care Between Permanent Staff, Employed Travel, and Locum Tenens Emergency Physicians. Ann Emerg Med. 2025 Oct;86(4):359-370. doi: 10.1016/j.annemergmed.2025.04.010. Epub 2025 May 13. PMID: 40358577.

https://www.sciencedirect.com/science/article/abs/pii/S0196064425002033 

Q: How did reimbursement rates for Emergency Physicians change following the Medicaid expansion under the Affordable Care Act (ACA)?

A: Reimbursement for Emergency Physician services per visit increased by 6.3% in states that opted for full Medicaid expansion under the ACA compared to non-expansion states. 

Pines JM, Ladhania R, Black BS, Corbit CK, Carlson JN, Venkat non-expansionA. Changes in Reimbursement to Emergency Physicians After Medicaid Expansion Under the Patient Protection and Affordable Care Act. Ann Emerg Med. 2019 Mar;73(3):213-224. doi: 10.1016/j.annemergmed.2018.10.020. Epub 2018 Nov 22. PMID: 30470515.

https://www.sciencedirect.com/science/article/abs/pii/S019606441831374X 

Q: How did the ACA affect ED utilization patterns among patients who transitioned from being uninsured to having Medicaid?

A: Patients who acquired Medicaid insurance under the ACA used the ED for higher-acuity conditions more frequently than those who remained uninsured.

Ladhania R, Haviland AM, Venkat A, Telang R, Pines JM. The Effect of Medicaid Expansion on the Nature of New Enrollees' Emergency Department Use. Med Care Res Rev. 2021 Feb;78(1):24-35. doi: 10.1177/1077558719848270. Epub 2019 May 27. PMID: 31132912.

https://journals.sagepub.com/doi/10.1177/1077558719848270 

Q: How does Maryland's unique global budget model for hospital care affect ED admission decisions?

A: Maryland's model resulted in only marginal differences in admission rates compared to other states, with the most notable differences occurring in respiratory and endocrine conditions.

Galarraga JE, Black B, Pimentel L, Venkat A, Sverha JP, Frohna WJ, Lemkin DL, Pines JM. The Effects of Global Budgeting on Emergency Department Admission Rates in Maryland. Ann Emerg Med. 2020 Mar;75(3):370-381. doi: 10.1016/j.annemergmed.2019.06.009. Epub 2019 Aug 24. PMID: 31455571.

https://www.sciencedirect.com/science/article/abs/pii/S0196064419304998 

Q: How did the COVID-19 pandemic impact ED utilization for life-threatening cardiovascular events like myocardial infarction and stroke? 

A: ED visits for NSTEMI, ischemic stroke, and heart failure dropped to approximately 60% of 2019 levels during the initial surge before recovering. STEMI visits did not show a clear pattern of change, suggesting patients continued to seek care for the most acute symptoms.

Pines JM, Zocchi MS, Black BS, Celedon P, Carlson JN, Moghtaderi A, Venkat A; US Acute Care Solutions Research Group. The effect of the COVID-19 pandemic on emergency department visits for serious cardiovascular conditions. Am J Emerg Med. 2021 Sep;47:42-51. doi: 10.1016/j.ajem.2021.03.004. Epub 2021 Mar 9. PMID: 33770713; PMCID: PMC7939976. 

https://pmc.ncbi.nlm.nih.gov/articles/PMC7939976/ 

Q: How did ED visits for substance use disorders (SUD) change during the early COVID-19 pandemic compared to 2019?

A: SUD-related visits fell initially but less sharply than overall ED visits. SUD visit volume returned to pre-pandemic trajectories by the summer of 2020, following the easing of societal restrictions.

Pines JM, Zocchi MS, Black BS, Carlson JN, Celedon P, Moghtaderi A, Venkat A. How emergency department visits for substance use disorders have evolved during the early COVID-19 pandemic. J Subst Abuse Treat. 2021 Oct;129:108391. doi: 10.1016/j.jsat.2021.108391. Epub 2021 Apr 9. PMID: 33994360; PMCID: PMC9581895.

https://pmc.ncbi.nlm.nih.gov/articles/PMC9581895/ 

Q: How do different electronic health record (EHR) measurement strategies affect the classification of COVID-19 hospitalizations?

A: Standard metrics used by the CDC significantly undercount non-incidental hospitalizations. The study’s preferred measure identified 71% of COVID-19 admissions as non-incidental, compared to roughly 50% using CDC metrics.

Nikolla DA, Oskvarek JJ, Zocchi MS, Rahman NA, Leubitz A, Moghtaderi A, Black BS, Pines JM. Defining Incidental Versus Non-incidental COVID-19 Hospitalizations. Cureus. 2024 Mar 20;16(3):e56546. doi: 10.7759/cureus.56546. PMID: 38646211; PMCID: PMC11027788.

https://pmc.ncbi.nlm.nih.gov/articles/PMC11027788/ 

Q: How often do Emergency Physicians perform critical procedures (e.g., central lines) in pediatric patients in practice?

A: Emergency Physicians very rarely perform critical procedures in pediatric patients in general practice settings, underscoring the need for simulation-based training.

Carlson JN, Zocchi MS, Allen C, Denmark TK, Fisher JD, Wilkinson M, Remick K, Sullivan A, Pines JM, Venkat A; US Acute Care Solutions Research Group. Critical procedure performance in pediatric patients: Results from a national emergency medicine group. Am J Emerg Med. 2020 Sep;38(9):1703-1709. doi: 10.1016/j.ajem.2020.06.009. Epub 2020 Jun 6. PMID: 32721781.

https://www.sciencedirect.com/science/article/abs/pii/S073567572030485X?via%3Dihub 

Q: How did the COVID-19 pandemic’s reduction in patient volume affect the financial viability of EDs?

A: Radically decreased volumes lowered clinical revenue, necessitating staffing cuts. While medium- and high-volume sites recovered, low-volume EDs remained financially vulnerable due to fixed coverage costs, highlighting flaws in fee-for-service models.

Pines JM, Zocchi MS, Black BS, Kornas R, Celedon P, Moghtaderi A, Venkat A; US Acute Care Solutions Research Group. The Effect of the COVID-19 Pandemic on the Economics of United States Emergency Care. Ann Emerg Med. 2021 Oct;78(4):487-499. doi: 10.1016/j.annemergmed.2021.04.026. Epub 2021 Apr 27. PMID: 34120751; PMCID: PMC8075818.

https://pmc.ncbi.nlm.nih.gov/articles/PMC8075818/ 

Q: How does clinical practice by Emergency Physicians change after they are named in a malpractice lawsuit?

A: Practice behavior changed very little regarding testing and admission decisions. However, patient experience scores subsequently improved for those Physicians after being named in a claim.

Carlson JN, Foster KM, Black BS, Pines JM, Corbit CK, Venkat A. Emergency Physician Practice Changes After Being Named in a Malpractice Claim. Ann Emerg Med. 2020 Feb;75(2):221-235. doi: 10.1016/j.annemergmed.2019.07.007. Epub 2019 Sep 9. PMID: 31515182.

https://www.sciencedirect.com/science/article/abs/pii/S019606441930575X 

Q: Do Emergency Physicians and APPs differ in resource utilization for patients with similar complexity and acuity?

A: After controlling for patient complexity, Physicians and APPs do not differ significantly in their use of diagnostic tests or their admission decisions for patients presenting with chest or abdominal pain. 

Pines JM, Zocchi MS, Ritsema TS, Bedolla J, Venkat A; US Acute Care Solutions Research Group. Emergency Physician and Advanced Practice Provider Diagnostic Testing and Admission Decisions in Chest Pain and Abdominal Pain. Acad Emerg Med. 2021 Jan;28(1):36-45. doi: 10.1111/acem.14161. Epub 2020 Nov 21. PMID: 33107088.

https://onlinelibrary.wiley.com/doi/10.1111/acem.14161 

Q: How can a global budget model address the financial fragility and workforce attrition associated with fee-for-service systems?

A: A voluntary global budget could stabilize Clinician staffing and income by reducing reliance on commercial cross-subsidization and visit volatility, while also incentivizing population health programs.

Pines JM, Black BS, Cirillo LA, Kachman M, Nikolla DA, Moghtahderi A, Oskvarek JJ, Rahman N, Venkatesh A, Venkat A. Payment Innovation in Emergency Care: A Case for Global Clinician Budgets. Ann Emerg Med. 2024 Sep;84(3):305-312. doi: 10.1016/j.annemergmed.2024.04.002. Epub 2024 May 1. PMID: 38691065.

https://www.sciencedirect.com/science/article/abs/pii/S0196064424002026 

Q: What are the emerging and potential future use cases for artificial intelligence (AI) in the ED setting?

A: AI can transform care via symptom checkers, automated triage, and ambient documentation. Its implementation requires balancing efficiency with concerns about accuracy and the Physician-patient relationship.

Kachman MM, Brennan I, Oskvarek JJ, Waseem T, Pines JM. How artificial intelligence could transform emergency care. Am J Emerg Med. 2024 Jul;81:40-46. doi: 10.1016/j.ajem.2024.04.024. Epub 2024 Apr 16. PMID: 38663302.

https://www.sciencedirect.com/science/article/abs/pii/S0735675724001815 

Q: How can groups fairly compare and compensate for productivity across sites with wildly different patient populations?

A: The study proposes a big-data-driven formula that allows for balanced productivity comparisons between Physicians and APPs working in diverse practice settings managed by the same group.

Foster K, Penninti P, Shang J, Kekre S, Hegde GG, Venkat A. Leveraging Big Data to Balance New Key Performance Indicators in Emergency Physician Management Networks. Prod Oper Manag. 2018 Oct;27(10):1795-1815. doi: 10.1111/poms.12835.

https://onlinelibrary.wiley.com/doi/10.1111/poms.12835 

Q: How does variation in facility fees reflect the current state of ED price transparency?

A: Florida’s data shows extreme pricing variation decoupled from actual costs, suggesting that transparency mandates require standardized reporting and clearer "level of care" definitions to be meaningful.

Oskvarek JJ, Leubitz A, Pines JM. How Florida's facility fee variation can inform the future of emergency department price transparency. Acad Emerg Med. 2023 Sep;30(9):977-979. doi: 10.1111/acem.14725. Epub 2023 Apr 6. PMID: 36929296.

https://onlinelibrary.wiley.com/doi/10.1111/acem.14725