Nicolaas Grobler Jr., MD

Medicare activity in 2024

Official CMS public-use data for Nicolaas Grobler Jr., 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.

Most frequent services

1. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)444 services
2. Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes (99232)373 services
3. Subsequent nursing facility care with moderate level of medical decision making, per day, if using time, at least 30 minutes (99309)172 services
4. Critical care, first 30-74 minutes (99291)146 services
5. Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more (99215)116 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 cholesterol75%
• Arthritis47%
• Diabetes45%
• Chronic kidney disease40%
• Heart failure39%

Hospitals where Nicolaas Grobler Jr. works

Medicare's Facility Affiliation Data lists Nicolaas Grobler Jr. 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.

• Casa Colina HospitalPomona, CA · Acute Care Hospital · Emergency services: not listed by Medicare · CCN 050782
• Montclair Hospital Medical CenterMontclair, CA · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 050758
• Pomona Valley Hospital Medical CenterPomona, CA · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 050231
• San Antonio Regional HospitalUpland, CA · Acute Care Hospital · Medicare rating: 3 of 5 stars · Emergency services: listed by Medicare · CCN 050099

Practice locations

Addresses where Nicolaas Grobler Jr. is enrolled with Medicare (CMS data updated October 2, 2026).

• 255 E Bonita AvePomona, CA 91767 (909) 626‑1205
• 350 S Euclid Ave, Suite CUpland, CA 91786 (909) 591‑6575
• 9525 Monte Vista Ave, Suite 105Montclair, CA 91763 (909) 626‑1205

Group practices

Medicare enrollment lists Nicolaas Grobler Jr. as a member of these groups (CMS data updated October 2, 2026).

• Inland Physicians Pulmonary Services7 clinicians in the group
• Grobler Enterprises Inc3 clinicians in the group

Specialties

• Pulmonary Diseaseprimary
• Critical Care (Intensivists)also
• Internal Medicinealso

Find other Pulmonary Disease doctors in California →

Other pulmonologists in Pomona

Clinicians with the same Medicare primary specialty in Pomona, CA — not a recommendation.

• Rakesh Sinha, MD
• Jaspreet S. Ahuja, MD
• Derrick N. Raptis, MD
• Owais A. Zaidi, MD
• Khader K. Abounasr, MD
• Dallis Q. Ngo, DO
• Elbert Chang, MD
• Rick Siriratsivawong, MD

All pulmonologists in Pomona →

Other clinicians in Inland Physicians Pulmonary Services

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

• Rick Siriratsivawong, MD
• John Kim, DO
• Calvin A. He, DO

Clinician information

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

1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
6. Medicare Care Compare — official Medicare tool to look up clinicians