NPPES file of Aug 9, 2026

Karen B. Alderfer, MD

Diagnostic Radiology Physician · Fort Collins, CO

Karen B. Alderfer, MD is a diagnostic radiology physician with a practice address in Fort Collins, Colorado, and NPI 1043534654, issued on Mar 25, 2010. Check the license (Colorado CDR.0001517, as entered in NPPES) on the Colorado Medical Board; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · Medicare files 2023 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1043534654
Name
Karen B. Alderfer
Credential
MD
Primary taxonomy
Diagnostic Radiology Physician 2085R0202X
License numbers
CDR.0001517 CO
16586 NV
A121137 CA
34356 NE
14311C WY
Self-reported in NPPES; status is on the state search
Practice location
1024 S Lemay Ave, Fort Collins, CO 80524
Phone
(970) 484-4757
Enumerated
Mar 25, 2010
Record last updated
Jul 1, 2025
Fax
(970) 484-4759
Medicare enrollment
Enrolled (PECOS I20160823001505); accepts Medicare assignment
Medical or professional school
University Of Nevada School Of Medicine, 2010
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
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Also registered at 1024 S Lemay Ave

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Guy Alexander, MDDiagnostic Radiology Physician1083989362
  2. Michael ApostleEmergency Medicine Physician1952326407
  3. Carlos ArguellesEmergency Medicine Physician1417962960
  4. Everett AustinEmergency Medicine Physician1548503758
  5. Alvis Ayaba-Apawu, M.A., PHD. LPC.LAC.Professional Counselor1154553691
  6. Bree Bacalis, NPNurse Practitioner1659861359

Verify Karen B. Alderfer in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersColorado Medical Board
    Search for license CDR.0001517
    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Open the Colorado license search

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The practice group's MIPS final score for 2023 (Medicare payment program): 84.4 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.

  1. Qualityout of 100 · 30% of the final score88.3
  2. Costout of 100 · 30%69.5
  3. Promoting interoperabilitynot scored (reweighted)
  4. Improvement activities40 of 40 points · 15%100.0

Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).

Bills Medicare through 2 group practices

  1. Fort Collins Radiologic Associates PCLas Vegas, NV
  2. Uchealth Imaging Services LLCDenver, CO

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

Diagnostic Radiology Physician providers in Colorado

There are 796 diagnostic radiology physician records in Colorado.

Other diagnostic radiology physician records in Colorado

  1. David Abbott, MDPueblo, CO1841421344
  2. Kent Abbott, M.D.Usaf Academy, CO1780668798
  3. William Abraham, M.D.Usaf Academy, CO1730161563
  4. Steven Abrams, MDDenver, CO1366402356
  5. Simeon Abramson, MDEnglewood, CO1730129859
  6. Mitchell Achee, M.D.Lakewood, CO1598891244
  7. Kim Adcock, MDDenver, CO1477696920
  8. Ajay Agarwal, M.D.Aurora, CO1043406242
  9. Michael Aidi, MDAurora, CO1386024354
  10. Mehmet Aksakal, M.D.Aurora, CO1316515679

Common questions

What is Karen B. Alderfer, MD's NPI number?

Karen B. Alderfer, MD's National Provider Identifier (NPI) is 1043534654, issued on Mar 25, 2010. An NPI identifies a provider in billing; it is not a license.

Where is Karen B. Alderfer, MD located?

The NPPES record lists a practice address at 1024 S Lemay Ave, Fort Collins, CO, 80524. Phone: (970) 484-4757. Providers update this record themselves, so call before visiting.

How can I verify Karen B. Alderfer, MD's license?

NPPES lists Colorado license number CDR.0001517, as entered by the provider. Search the Colorado Medical Board at https://dpo.colorado.gov/Medical. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

What is Karen B. Alderfer, MD's MIPS final score?

The 2023 MIPS final score is 84.4 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.