DR. RUBY CHANG M.D.
NPI 1164459335
Radiology - Diagnostic Radiology in Walnut Creek, CA

Q: What is Ruby Chang's NPI number?

The NPI number for Ruby Chang is 1164459335. It was assigned to this individual provider in the NPPES registry on June 26, 2006.

Q: What is Ruby Chang's specialty?

The primary specialty registered for this NPI is Radiology, specializing in Diagnostic Radiology, with taxonomy code 2085R0202X.

Q: When was this NPI record last updated?

The NPPES record for Ruby Chang was last updated on April 2, 2015. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.

Active since June 26, 2006PECOS EnrolledAccepts Medicare Assignment

2125 OAK GROVE RD, SUITE 200, WALNUT CREEK, CA 94598(925) 296-7150(925) 296-7171 Get Directions Write a Review

NPPES record last updated: April 2, 2015. Verified against the NPPES registry weekly; last sync: October 18, 2026.

On this page

About Dr. Ruby Chang M.d. NPPES

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

DR. RUBY CHANG M.D. (NPI 1164459335) is an individual diagnostic radiology provider in Walnut Creek, California, licensed in California (A81716) and active in the NPI registry since June 2006. She is enrolled in Medicare PECOS, is affiliated with University Of Md Baltimore Washington Medical Center, and is a graduate of Rutgers New Jersey Medical School (1998).

NPPES Registry Identity

NPI1164459335

Entity TypeIndividualFemale

Primary Taxonomy2085R0202X

Provider Legal NameDR. RUBY CHANGCredential: M.D.

Location Address2125 OAK GROVE RD, SUITE 200Walnut Creek, CA 94598-2536

Mailing Address2125 Oak Grove Rd, Suite 200Walnut Creek, CA 94598-2536 · (925) 296-7150 · Fax (925) 296-7171

Phone(925) 296-7150

Fax(925) 296-7171

Sole ProprietorNo

Medical School CMSRutgers New Jersey Medical SchoolGraduated 1998

Enumeration DateJune 26, 2006

Last NPPES UpdateApril 2, 2015

✔ NPI 1164459335 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyRadiology · Diagnostic RadiologyAllopathic & Osteopathic Physicians

Taxonomy Code2085R0202X

License✔ Licensed in CA · A81716

Definition

A radiologist who utilizes x-ray, radionuclides, ultrasound and electromagnetic radiation to diagnose and treat disease.

2125 OAK GROVE RD, Walnut Creek, CA 94598

Open in Google Maps ↗

Other Identifiers 24

Medicare PINP00197714CA

Medicare PIN00A8171615CA

Medicare PIN00A8171612CA

Medicare PIN00A8171619CA

Medicare PIN00A8171621CA

Medicare PIN00A817167CA

Medicare PIN00A817165CA

Medicare PIN00A8171614CA

Medicare UPINH82700CA

Medicare PIN00A8171620CA

Medicare PIN00A8171610CA

Medicare PIN00A8171613CA

Medicare PIN00A817169CA

Medicare PINP00133300CA

Medicare PIN00A8171616CA

Medicare PIN00A817162CA

Medicare PIN00A817163CA

Medicare PIN00A817161CA

Medicare PIN00A817166CA

Medicare PIN00A817168CA

Medicare PIN00A8171618CA

Medicare PIN00A8171611CA

Medicare PIN00A8171617CA

Medicare PIN00A8171622CA

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dr. Ruby Chang 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 ID7719966241

PECOS Enrollment IDI20220425001348

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.

Medicare Billing Reassignments

Medicare enrollment records show Ruby Chang reassigns Medicare billing to 6 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Bay Imaging Consultants Medical Group Inc

Same address

Diagnostic Radiology

2125 OAK GROVE RD STE 200
Walnut Creek, CA 94598

Reassigned Medicare billing, California enrollment
181 clinicians in this Medicare group

NPI 1831756139 (925) 296-7150

John Muir Trauma Physicians Billing Service

1.7 mi

Trauma Surgery

1601 YGNACIO VALLEY RD
Walnut Creek, CA 94598

Reassigned Medicare billing, California enrollment
810 clinicians in this Medicare group

NPI 1962551861 (925) 947-5331

Epic Care

12 mi

Multi-Specialty

4721 DALLAS RANCH RD
Antioch, CA 94531

Reassigned Medicare billing, California enrollment
86 clinicians in this Medicare group

NPI 1780107797 (925) 778-0679

Magnetic Imaging Affiliates, LLC

15 mi

Diagnostic Radiology

5730 TELEGRAPH AVE
Oakland, CA 94609

Reassigned Medicare billing, California enrollment
158 clinicians in this Medicare group

NPI 1487040770 (510) 204-2744

Solano Diagnostics Partners, A Calif Limited Partnership

21 mi

Diagnostic Radiology

4500 BUSINESS CENTER DR
Fairfield, CA 94534

Reassigned Medicare billing, California enrollment
88 clinicians in this Medicare group

NPI 1972006534 (855) 820-5256

Advanced Radiology P A

2,409 mi

Diagnostic Radiology

193 STONER AVE STE 200
Westminster, MD 21157

Reassigned Medicare billing, Maryland enrollment
128 clinicians in this Medicare group

NPI 1922825892 (888) 972-9700

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 29

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.

Injection, gadoterate meglumine, 0.1 ml A9575

Gadoterate meglumine is a contrast agent used in MRI scans to help visualize certain areas of your body more clearly. It's injected into your bloodstream, typically through a vein in your arm, and helps doctors get more detailed images.

9,480 services56 patients

Screening 3d breast mammography 77063

Screening 3D breast mammography is a procedure that uses low-dose X-rays to create detailed images of the breast. This allows for early detection of any unusual changes or growths. It's a non-invasive, outpatient procedure that typically takes about 30 minutes.

3,410 services3,410 patients

Screening mammography 77067

Screening mammography is a preventative measure that uses low-dose X-rays to take images of the chest area. It's a key tool in early detection of abnormalities, helping to identify issues before they become symptomatic. It is recommended annually for certain age groups.

3,406 services3,406 patients

Low osmolar contrast material, 300-399 mg/ml iodine concentration, per ml Q9967

Low osmolar contrast material with 300-399 mg/ml iodine concentration is a diagnostic tool used in imaging procedures. It helps to enhance the visibility of specific areas in the body, aiding in accurate diagnosis. It's safe and generally well-tolerated by patients.

1,680 services21 patients

Diagnostic digital breast tomosynthesis, unilateral or bilateral (list separately in addition to 77065 or 77066) G0279

Diagnostic digital breast tomosynthesis is a 3D imaging test that allows doctors to examine your breast tissue layer by layer. It's performed on one or both sides. It helps in detecting abnormalities more accurately. It's often done in addition to other tests.

345 services344 patients

Diagnostic mammography of 1 breast 77065

Diagnostic mammography of 1 breast is a detailed imaging test that allows doctors to closely examine a specific area in the breast. It's often used when a routine screening reveals an abnormality. This test can help identify any unusual changes or issues.

240 services236 patients

Limited ultrasound scan of 1 breast 76642

A limited ultrasound scan of one breast is a non-invasive imaging test. It uses sound waves to create pictures of the inside of your breast. It helps identify any unusual growths or changes. It's safe, quick, and typically painless.

229 services227 patients

Diagnostic mammography of both breasts 77066

Diagnostic mammography involves using special imaging technology to capture detailed images of both breasts. This procedure helps in identifying any unusual changes or abnormalities. It's a crucial step in ensuring breast health and early detection of potential issues.

205 services204 patients

X-ray of chest, 1 view 71045

A chest X-ray, 1 view, is a quick, painless test that produces images of the structures within your chest, such as your heart, lungs, and blood vessels. It helps in diagnosing conditions like pneumonia, heart problems, or lung cancer. You'll stand in front of a machine that emits X-rays, which pass through your body to create the image.

166 services152 patients

Dxa bone density measurement of hip, pelvis, spine 77080

A DXA bone density measurement is a simple, quick, and non-invasive procedure that assesses the strength of your bones. This test uses X-rays to measure the amount of minerals, mainly calcium, in the hip, pelvis, and spine. It helps in early detection of osteoporosis or other bone diseases.

89 services89 patients

Ct scan head or brain without contrast 70450

A CT scan of the head or brain without contrast is a non-invasive imaging procedure. It uses X-rays to create detailed pictures of your brain, skull, and other structures inside your head. It helps to detect conditions like strokes, tumors, or injuries. No dye (contrast) is used in this test.

69 services67 patients

X-ray of chest, 2 views 71046

A chest X-ray, 2 views, is a quick, painless test that creates pictures of the structures inside your chest, such as your heart, lungs, and blood vessels. Two different angles are used to get a comprehensive view. This helps in diagnosing conditions like pneumonia, heart problems, or lung cancer.

69 services69 patients

Mri scan of both breasts 77049

An MRI scan of both breasts is a non-invasive procedure using magnetic fields and radio waves to create detailed images of your chest area. This aids in detecting any abnormalities, ensuring your health and well-being.

54 services53 patients

Ct scan of abdomen and pelvis with contrast 74177

A CT scan of the abdomen and pelvis with contrast is an imaging procedure. A special dye, called contrast, is used to make certain areas more visible. This can help identify issues such as infections, tumors, or other abnormalities. The procedure is painless and usually takes about 30 minutes.

38 services38 patients

Ct scan of blood vessels of chest with contrast 71275

A CT scan of the chest with contrast is a non-invasive imaging test. It uses X-rays and a special dye to get detailed images of your blood vessels in the chest. This helps in diagnosing conditions related to heart and lungs.

37 services37 patients

Dxa bone density measurement of forearm, finger, hand, or foot 77081

A DXA bone density measurement of the forearm, finger, hand, or foot is a non-invasive procedure that uses X-rays to measure the amount of calcium and other minerals in your bones. This test helps to assess the strength of your bones and your risk of fractures.

37 services37 patients

Biopsy of breast and placement of locating device using ultrasound, first growth 19083

A breast biopsy with locating device placement involves taking a small sample from an unusual growth, using ultrasound for precise targeting. This sample is studied for any abnormal cells. A locating device is also placed to mark the area for future reference.

30 services30 patients

X-ray of chest, 2 views 71046

24 services24 patients

Ct scan of upper spine without contrast 72125

A CT scan of the upper spine without contrast is a non-invasive imaging test that uses X-rays to capture detailed images of your neck and upper back. It helps in identifying issues like fractures, tumors, or infections. No dye (contrast) is used in this scan.

23 services23 patients

Biopsy of breast and placement of locating device using x-ray with needle, first growth 19081

A biopsy of the breast involves extracting a small sample of tissue for examination. A locating device placement, guided by x-ray, aids in identifying the exact spot of the first growth. A needle is used in both processes to ensure precision and minimal discomfort.

21 services21 patients

Ct scan of abdomen and pelvis without contrast 74176

A CT scan of the abdomen and pelvis is a non-invasive medical test. It uses special X-ray equipment to create detailed images of your abdominal and pelvic areas. This helps doctors examine organs, tissues, and vessels. No contrast dye is used in this procedure.

21 services21 patients

Ct scan of chest without contrast 71250

A CT scan of the chest without contrast is a non-invasive imaging procedure. It uses special X-ray equipment to produce detailed images of your chest area, including your lungs and heart. It can help diagnose conditions such as lung diseases or heart disorders. It doesn't involve any dyes or contrast agents.

20 services20 patients

Ct scan of blood vessels of head with contrast 70496

A CT scan of the head's blood vessels with contrast is a diagnostic procedure. A special dye (contrast) is injected into your body to make the blood vessels visible on the scan. This helps identify issues like blockages or abnormalities in your head's blood vessels.

16 services16 patients

Ct scan of blood vessels of neck with contrast 70498

A CT scan of the neck's blood vessels with contrast is a diagnostic procedure. It uses X-rays and a special dye to create detailed images of your neck's blood vessels. This helps doctors detect issues such as blockages or abnormalities.

16 services16 patients

Complete ultrasound scan of 1 breast 76641

A complete ultrasound scan of one breast is a non-invasive imaging test that uses sound waves to create detailed images of the inside of your breast. It helps in detecting any abnormalities or changes, ensuring your breast health.

13 services13 patients

Ct scan of chest with contrast 71260

A CT scan of the chest with contrast is an imaging procedure. A special dye (contrast) is used to highlight specific areas in your body, providing clearer pictures of your chest. This helps in diagnosing conditions related to your lungs, heart, and other chest structures.

12 services12 patients

Ct scan of blood vessels of abdomen and pelvis with contrast 74174

A CT scan of the abdomen and pelvis with contrast is a medical imaging procedure. A special dye, called contrast, is used to make blood vessels more visible. The scan produces detailed images of your abdomen and pelvis, helping doctors to diagnose conditions or plan treatments.

12 services12 patients

Ct scan of chest without contrast 71250

11 services11 patients

Ct scan of abdomen and pelvis with contrast 74177

11 services11 patients

Hospital Affiliations CMS Care Compare 3

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

University Of MD Baltimore Washington Medical Center

Acute Care Hospitals · Glen Burnie, MD

3/5 CMS rating

OwnershipVoluntary non-profit - Other

CMS Certification Number210043

Location301 Hospital DriveGlen Burnie, MD 21061 · Anne Arundel County

Emergency services Birthing friendly

Umd Upper Chesapeake Medical Center

Acute Care Hospitals · Bel Air, MD

2/5 CMS rating

OwnershipVoluntary non-profit - Other

CMS Certification Number210049

Location500 Upper Chesapeake DriveBel Air, MD 21014 · Harford County

Emergency services Birthing friendly

University Of MD St Joseph Medical Center

Acute Care Hospitals · Towson, MD

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number210063

Location7601 Osler DriveTowson, MD 21204 · Baltimore County

Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94598 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.

Reported Quality Measures

Radiation Consideration for Adult CT: Utilization of Dose Lowering Techniques

Percentage of final reports for patients aged 18 years and older undergoing CT with documentation that one or more of the following dose reduction techniques were used: - Automated exposure control - Adjustment of the mA and/or kV according to patient size -…

100%87 patients

Radiology: Reminder System for Screening Mammograms

Percentage of patients undergoing a screening mammogram whose information is entered into a reminder system with a target due date for the next mammogram

100%72 patients

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.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

DR. PHILIP J. RICH MD

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, #200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

DR. JONATHAN FISH M.D.

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

DR. JOSEPH CHAN M.D.

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

DR. ASEEM OM RAWAL M.D.

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

CHRISTOPHER C LEE MD

Radiology (Vascular & Interventional Radiology)

2125 OAK GROVE RD, #200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

SUNIL GANDHI M.D.

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

DR. RALPH WESLEY MUTCHLER M.D.

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, #200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

DR. SANGEETA GAMBHIR M.D.

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, #200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

MARK KUANG-MIAN TU M.D.

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

DR. RONALD CHAN M.D.

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

DR. KEYVAN NOURI M.D.

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

JOAN REYNOLDS M.D.

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

KEITH EDWIN-MOSUN TAO M.D.

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-1756

ANGELO CRUDALE MD

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

DR. NORMAN MOSCOW

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

STEPHEN HESSELTINE M.D.

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

SIVA P RAMAN

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, STE 200
WALNUT CREEK, CA 94598

Contra Costa County (410) 955-5173

DR. DANIEL KIM M.D.

Radiology (Vascular & Interventional Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

DR. KIMBERLY M. BLUMBERG M.D

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

DR. YING FUNG M.D.

Radiology (Diagnostic Radiology)

2125 OAK GROVE RD, SUITE 200
WALNUT CREEK, CA 94598

Contra Costa County (925) 296-7150

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 Ruby Chang's NPI number?

The NPI number for Ruby Chang is 1164459335. It was assigned to this individual provider in the NPPES registry on June 26, 2006.

Where is Ruby Chang located?

Ruby Chang practices at 2125 Oak Grove Rd Suite 200, Walnut Creek, CA 94598. The listed phone number is (925) 296-7150.

What is Ruby Chang's specialty?

The primary specialty registered for this NPI is Radiology, specializing in Diagnostic Radiology, with taxonomy code 2085R0202X.

Is Ruby Chang enrolled in Medicare?

Yes. Ruby Chang 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.

Which organizations bill Medicare for Ruby Chang's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Ruby Chang reassigns Medicare benefits to 6 organizations: Bay Imaging Consultants Medical Group Inc (Walnut Creek, CA), John Muir Trauma Physicians Billing Service (Walnut Creek, CA), Epic Care (Antioch, CA), Magnetic Imaging Affiliates, LLC (Oakland, CA), Solano Diagnostics Partners, A Calif Limited Partnership (Fairfield, CA) and 1 more organization, listed in the Medicare section above. Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Ruby Chang's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

Is Ruby Chang affiliated with any hospitals?

According to CMS data, Ruby Chang is affiliated with University Of MD Baltimore Washington Medical Center, Umd Upper Chesapeake Medical Center and University Of MD St Joseph Medical Center.

When was this NPI record last updated?

The NPPES record for Ruby Chang was last updated on April 2, 2015. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.