Quick answers
- Does Karl Gaal accept Medicare assignment?
- Yes. Medicare's clinician data says Karl Gaal accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Karl Gaal see?
- In 2024, CMS data shows 781 Original Medicare patients and 4,012 services for Karl Gaal. This counts Original Medicare only and measures volume, not quality.
- What is Karl Gaal's NPI number?
- 1710943543. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Karl Gaal, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 781 |
|---|---|
| Services billed to Medicare | 4,012 |
| Different services or procedures | 26 |
| Participating Medicare provider | Yes |
| Average age of these patients | 72 |
Most frequent services
- Special stained specimen slides to examine tissue, each additional procedure (88341)1,020 services
- Protein measurement, serum (84165)617 services
- Pathology examination of tissue using a microscope, intermediate complexity (88305)426 services
- Immunologic analysis technique on serum (immunofixation) (86334)302 services
- Special stained specimen slides to examine tissue, initial procedure (88342)235 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High blood pressure75%
- High cholesterol69%
- Arthritis44%
- Diabetes34%
- Ischemic heart disease34%
- Chronic kidney disease34%
Hospitals where Karl Gaal works
Medicare's Facility Affiliation Data lists Karl Gaal at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- Hoag Memorial Hospital PresbyterianNewport Beach, CA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 050224
- Providence Mission HospitalMission Viejo, CA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 050567
- UC San Diego Health Hillcrest - Hillcrest Medical CenterSan Diego, CA · Acute Care Hospital · Medicare rating: 5 of 5 stars · Emergency services: listed by Medicare · CCN 050025
- UCI Health-OrangeOrange, CA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 050348
Practice locations
Addresses where Karl Gaal is enrolled with Medicare (CMS data updated October 2, 2026).
- 1500 Duarte RdDuarte, CA 91010 (626) 256‑4673
- 1500 E Duarte RdDuarte, CA 91010
- 209 Fair Oaks AveSouth Pasadena, CA 91030 (626) 396‑2900
Group practices
Medicare enrollment lists Karl Gaal as a member of this group (CMS data updated October 2, 2026).
- City of Hope Medical Foundation982 clinicians in the group
Specialties
- Pathologyprimary
Other pathologists in Duarte
Clinicians with the same Medicare primary specialty in Duarte, CA — not a recommendation.
Other clinicians in City of Hope Medical Foundation
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of California, Davis School Of Medicine |
| Graduation year | 1994 (32 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1710943543 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians