Quick answers
- Does Holly N. Maas accept Medicare assignment?
- Yes. Medicare's clinician data says Holly N. Maas 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 Holly N. Maas see?
- In 2024, CMS data shows 28 Original Medicare patients and 500 services for Holly N. Maas. This counts Original Medicare only and measures volume, not quality.
- What is Holly N. Maas's NPI number?
- 1033159660. 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 Holly N. Maas, 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 | 28 |
|---|---|
| Services billed to Medicare | 500 |
| Different services or procedures | 7 |
| Participating Medicare provider | Yes |
| Average age of these patients | 56 |
Most frequent services
- Psychotherapy, 45 minutes (90834)326 services
- Psychotherapy, 1 hour (90837)102 services
- Psychotherapy, 30 minutes (90832)22 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).
- Depression75%
- Anxiety75%
- High blood pressure57%
- High cholesterol39%
- Arthritis39%
Hospitals where Holly N. Maas works
Medicare's Facility Affiliation Data lists Holly N. Maas 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.
- University of Iowa Hospital & ClinicsIowa City, IA · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 160058
Practice locations
Addresses where Holly N. Maas is enrolled with Medicare (CMS data updated October 2, 2026).
- 200 Hawkins DrIowa City, IA 52242
Group practices
Medicare enrollment lists Holly N. Maas as a member of this group (CMS data updated October 2, 2026).
- State University of Iowa1,897 clinicians in the group
Specialties
- Clinical Social Workerprimary
Other clinical social workers in Iowa City
Clinicians with the same Medicare primary specialty in Iowa City, IA — not a recommendation.
Other clinicians in State University of Iowa
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Graduation year | 2002 |
|---|---|
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1033159660 |
| 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