Aaron John Lacy, MD
Emergency Medicine Physician · Saint Louis, MO
Aaron John Lacy, MD is an emergency medicine physician with a practice address in Saint Louis, Missouri, and NPI 1700374303, issued on Apr 29, 2018. Check the license (Missouri 2022019737, as entered in NPPES) on the Missouri Board of Registration for the Healing Arts; the Medicare figures below come from public CMS files.
- Name
- Aaron John Lacy
- Credential
- MD
- Primary taxonomy
- Emergency Medicine Physician 207P00000X
- License number
- 2022019737 MO
Self-reported in NPPES; status is on the state search - Practice location
- 1 Barnes Jewish Hospital Plz, Saint Louis, MO 63110
- Phone
- (314) 362-9123
- Enumerated
- Apr 29, 2018
- Record last updated
- Apr 17, 2025
- Fax
- (314) 362-0478
- Medicaid ID
- 200110256 MO
- Medicare enrollment
- Enrolled (PECOS I20220705001844); accepts Medicare assignment
- Medical or professional school
- University Of Iowa, Rj & L Carver College Of Medicine, 2018
- Entity
- Type 1 · individual
8 nearest emergency medicine physician records → All 1,405 in Missouri → Look up another NPI →
Also registered at 1 Barnes Jewish Hospital Plz
A shared address usually means a shared clinic or building; it does not show who employs whom.
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Verify Aaron John Lacy in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMissouri Board of Registration for the Healing Arts
Search for license 2022019737Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
68% fewer Medicare Part D claims than the average emergency medicine physician in 2024
72 Medicare Part D claims for 51 beneficiaries, against an average of 226 among the 54,106 providers of this specialty who prescribed in Part D. 12 claims were for opioids.
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
The practice group's MIPS final score for 2023 (Medicare payment program): 79.3 of 100
The Merit-based Incentive Payment System score is reported for the practice group, not for one clinician alone. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).
Bills Medicare through one group practice
- Washington UniversitySaint Louis, MO
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Aaron John Lacy among 1,405 emergency medicine physician records in Missouri
Aaron John Lacy, MD is one of 1,405 emergency medicine physician records with a practice address in Missouri. 80% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2018, is newer than 75% of them.
- NPI issued2018 · 75% of these records are older, 21% newer
- In a Medicare fileYes · 80% of these records are
- In the CMS Doctors and Clinicians fileYes · 58% of these records are
- Graduated2018 · median 2012 among the 808 with a school on file
- Record last updated2025 · 48% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207P00000X and a Missouri practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
398 emergency medicine physician records list a practice address in Saint Louis
They are 398 of the 27,605 NPPES records with a practice address in Saint Louis, and 1,405 emergency medicine physician records in Missouri.
All 1,405 in Missouri → Every provider in Saint Louis → Emergency Medicine Physician nationwide →
The 8 emergency medicine physician records with the nearest ZIP codes
- David Amin, MDSaint Louis, MO 631101528003787
- Brian Cohn, MDSaint Louis, MO 631101649206061
- Brian Froelke, MDSaint Louis, MO 631101114951233
- Gary Gambill, MDSaint Louis, MO 631101346282837
- Richard Griffey, MDSaint Louis, MO 631101023075405
- Kamal Gursahani, MDSaint Louis, MO 631101396760849
- Reuben Johnson, MDSaint Louis, MO 631101174563217
- Richard Schmidt, MDSaint Louis, MO 631101437133501
Common questions
What is Aaron John Lacy, MD's NPI number?
Aaron John Lacy, MD's National Provider Identifier (NPI) is 1700374303, issued on Apr 29, 2018. An NPI identifies a provider in billing; it is not a license.
Where is Aaron John Lacy, MD located?
The NPPES record lists a practice address at 1 Barnes Jewish Hospital Plz, Saint Louis, MO, 63110. Phone: (314) 362-9123. Providers update this record themselves, so call before visiting.
How can I verify Aaron John Lacy, MD's license?
NPPES lists Missouri license number 2022019737, as entered by the provider. Search the Missouri Board of Registration for the Healing Arts at https://www.fsmb.org/contact-a-state-medical-board/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Aaron John Lacy, MD prescribe under Medicare Part D?
In 2024, Aaron John Lacy, MD had 72 Medicare Part D claims for 51 beneficiaries; the average among emergency medicine physician prescribers was 226. Part D covers Medicare prescriptions only.
What is Aaron John Lacy, MD's MIPS final score?
The 2023 MIPS final score is 79.3 of 100, reported for the practice group. The average among 454,083 clinicians with a measured score was 83.5.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.