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DR. DIRK ROSS DIEFENDORF M.D.
NPI 1467559443
Neuromusculoskeletal Medicine, Sports Medicine in San Mateo, CA

Active since September 20, 2006PECOS EnrolledAccepts Medicare Assignment
99.99/100
CMS Quality Rating
101 S ELLSWORTH AVE, SUITE 607, SAN MATEO, CA 94401(650) 347-0157(650) 347-0566 Get Directions Write a Review

NPPES record last updated: August 30, 2010. Verified against the NPPES registry weekly; last sync: July 19, 2026.

About Dr. Dirk Ross Diefendorf M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. DIRK ROSS DIEFENDORF M.D. (NPI 1467559443) is an individual neuromusculoskeletal medicine, sports medicine provider in San Mateo, California, licensed in California (G53558) and active in the NPI registry since September 2006. He is enrolled in Medicare PECOS and is a graduate of Northwestern University Feinberg Medical School (1983).

NPPES Registry Identity

NPI1467559443
Entity TypeIndividualMale
Primary Taxonomy204C00000X
Provider Legal NameDR. DIRK ROSS DIEFENDORFCredential: M.D.
Location Address101 S ELLSWORTH AVE, SUITE 607San Mateo, CA 94401-3956
Mailing Address101 S Ellsworth Ave, Suite 607San Mateo, CA 94401-3956 · (650) 347-0157 · Fax (650) 347-0566
Phone(650) 347-0157
Fax(650) 347-0566
Sole ProprietorYes
Medical School CMSNorthwestern University Feinberg Medical SchoolGraduated 1983
Enumeration DateSeptember 20, 2006
Last NPPES UpdateAugust 30, 2010
✔ NPI 1467559443 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyNeuromusculoskeletal Medicine, Sports MedicineAllopathic & Osteopathic Physicians
Taxonomy Code204C00000X
License✔ Licensed in CA · G53558
Definition

A Neuromusculoskeletal Medicine and Osteopathic Manipulative Medicine physician trained to be responsible for the continuous care in the field of sports medicine encompasses increased knowledge and understanding of osteopathic principles and practice and heightened technical skills of osteopathic manipulative medicine and integrates each of these into the management of the individual engaged in physical exercise (sports) whether as an individual or in team participation. Source: American Osteopathic Association Additional Resources: AOA Osteopathic Board Certification in Neuromusculoskeletal Medicine; https://certification.osteopathic.org/sports-medicine/

101 S ELLSWORTH AVE, San Mateo, CA 94401
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Other Identifiers 2

Medicare UPINA93235CA
Medicare ID-Type Unspecified00G535580CA

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dr. Dirk Ross Diefendorf M.d. is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID648462390
PECOS Enrollment IDI20101013000318
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Areas of Expertise CMS Part B claims 5

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214
This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.
274 services160 patients
Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213
This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.
89 services57 patients
New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204
This is a first-time office or outpatient visit lasting between 45-59 minutes. The healthcare provider evaluates your health, discusses your medical history, and may suggest further tests or treatments. It's an opportunity to ask questions and understand your health better.
83 services83 patients
New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more 99203
This service involves an initial office or outpatient visit for a new patient. The healthcare professional will spend 30-44 minutes understanding your health history, current issues, and discussing possible treatment plans. It's a comprehensive evaluation to start your healthcare journey.
17 services17 patients
New patient office or other outpatient visit with a high level of medical decision making, if using time, 60 minutes or more 99205
This is a first-time patient visit where a healthcare professional spends 60-74 minutes with you. It involves a comprehensive evaluation, including your medical history and current health condition. They'll also advise on preventive health measures and formulate a treatment plan if needed.
11 services11 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94401 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$104.51 typical visit price
range $69.00 – $202.35
Typical copayment $26.12 (range $17.25 – $50.58)
Most-billed visit code 99203
Established Patient
$84.91 typical visit price
range $23.44 – $166.46
Typical copayment $21.22 (range $5.86 – $41.61)
Most-billed visit code 99213
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

99.99/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Individually scored
Quality99.98
Promoting Interoperability100
Improvement Activities40

Reported Quality Measures

Breast Cancer Screening
83%177 patients4/55-star benchmark: 93%
Cervical Cancer Screening
62%141 patients3/55-star benchmark: 98%
Closing the Referral Loop: Receipt of Specialist Report
16%129 patients1/55-star benchmark: 87%
Colorectal Cancer Screening
70%438 patients4/55-star benchmark: 88%
Controlling High Blood Pressure
76%247 patients4/55-star benchmark: 91%
Diabetes: Eye Exam
69%67 patients3/55-star benchmark: 100%
Diabetes: Hemoglobin A1c (HbA1c) Poor Control (>9%)
Lower rates are better for this measure.
13%67 patients4/55-star benchmark: 91%
Documentation of Current Medications in the Medical Record
92%1,647 patients4/55-star benchmark: 100%
e-Prescribing
100%352 patients5/55-star benchmark: 100%
Falls: Screening for Future Fall Risk
8%404 patients1/55-star benchmark: 100%
Preventive Care and Screening: Body Mass Index (BMI) Screening and Follow-Up Plan
32%766 patients2/55-star benchmark: 98%
Preventive Care and Screening: Screening for Depression and Follow-Up Plan
16%699 patients1/55-star benchmark: 97%
Preventive Care and Screening: Screening for High Blood Pressure and Follow-Up Documented
0%1,011 patients1/55-star benchmark: 61%
Preventive Care and Screening: Tobacco Use: Screening and Cessation Intervention
Patients screened: 98% · 456 patients
95%456 patients
Provide Patients Electronic Access to Their Health Information
100%875 patients5/55-star benchmark: 100%
Use of High-Risk Medications in Older Adults
Lower rates are better for this measure.
Patients appropriateDiagnosis: 9% · 421 patients
Patients totalRate: 15% · 421 patients
13%421 patients3/55-star benchmark: 100%
Providers report different measures because they deliver different services; reporting more or less information is not a reflection of quality. Star ratings appear only where CMS assigned them.

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Dirk Diefendorf's NPI number?

The NPI number for Dirk Diefendorf is 1467559443. It was assigned to this individual provider in the NPPES registry on September 20, 2006.

Where is Dirk Diefendorf located?

Dirk Diefendorf practices at 101 S Ellsworth Ave Suite 607, San Mateo, CA 94401. The listed phone number is (650) 347-0157.

What is Dirk Diefendorf's specialty?

The primary specialty registered for this NPI is Neuromusculoskeletal Medicine, Sports Medicine with taxonomy code 204C00000X.

Is Dirk Diefendorf enrolled in Medicare?

Yes. Dirk Diefendorf is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

When was this NPI record last updated?

The NPPES record for Dirk Diefendorf was last updated on August 30, 2010. NPI Profile syncs with the weekly NPPES data releases published by CMS.