Quick answers
- Does Donald A. Guillen accept Medicare assignment?
- Yes. Medicare's clinician data says Donald A. Guillen 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 Donald A. Guillen see?
- In 2024, CMS data shows 198 Original Medicare patients and 427 services for Donald A. Guillen. This counts Original Medicare only and measures volume, not quality.
- What is Donald A. Guillen's NPI number?
- 1871943613. 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 Donald A. Guillen, 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 | 198 |
|---|---|
| Services billed to Medicare | 427 |
| Different services or procedures | 5 |
| Participating Medicare provider | Yes |
| Average age of these patients | 77 |
Most frequent services
- Test to assess middle ear function (92567)196 services
- Comprehensive hearing and speech recognition test (92557)195 services
- Placement of ear probe for computerized measurement of repeated sounds with interpretation and report (92588)33 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 cholesterol75%
- High blood pressure68%
- Arthritis37%
- Ischemic heart disease27%
- Diabetes24%
- Osteoporosis21%
Practice locations
Addresses where Donald A. Guillen is enrolled with Medicare (CMS data updated October 2, 2026).
- 1447 York Rd, Suite 312Lutherville, MD 21093 (410) 583‑7021
Group practices
Medicare enrollment lists Donald A. Guillen as a member of this group (CMS data updated October 2, 2026).
- Hearing Assessment Center, LLC6 clinicians in the group
Specialties
- Qualified Audiologistprimary
Other audiologists in Lutherville
Clinicians with the same Medicare primary specialty in Lutherville, MD — not a recommendation.
Other clinicians in Hearing Assessment Center, LLC
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | AU |
|---|---|
| Graduation year | 2016 |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1871943613 |
| 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
- 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