William Asch, M.D., PH.D.
NPI 1003933326 · Nephrology Physician · New Haven, CT
Enrolled with Medicare as Practitioner - Nephrology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
William Asch, M.D., PH.D. is a Nephrology Physician provider in New Haven, CT (NPI 1003933326).
Provider details
- NPI number
- 1003933326
- Entity type
- Individual
- Primary specialty
- Nephrology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D., PH.D.
- Sex
- Male
- Sole proprietor
- No
- License
- 044496 (CT)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
19 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
560 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232 | 257 | $79 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 119 | $98 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 70 | $115 |
| Initial Hospital Care With Straightforward Or Low-Level Medical Decision Making, If Using Time, at Least 55 Minutes99222 | 47 | $133 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 25 | $121 |
| Needle Biopsy of Kidney50200 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 36 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Prednisone | 256 | 64 |
| Amlodipine Besylate | 135 | 45 |
| Carvedilol | 118 | 33 |
| Tamsulosin Hcl | 88 | 23 |
| Sulfamethoxazole/Trimethoprimbrand: Sulfamethoxazole-Trimethoprim | 80 | 20 |
| Metoprolol Tartrate | 66 | 14 |
| Famotidine | 62 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2007-03-23
- Last updated
- 2007-10-27
Frequently asked questions
- What is William Asch's NPI number?
- William Asch's National Provider Identifier (NPI) is 1003933326, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is William Asch's specialty?
- William Asch is listed in the NPPES registry with a primary specialty of Nephrology Physician (Allopathic & Osteopathic Physicians).
- Where is William Asch located?
- William Asch's practice location on file with NPPES is 20 York Street Cb 2041, New Haven, CT 06510.
- What is William Asch's phone number?
- The practice phone number listed in the NPPES registry for William Asch is (203) 688-4748.
- Does William Asch accept Medicare?
- William Asch is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is William Asch's NPI active?
- Yes — William Asch's NPI (1003933326) is active in the NPPES registry as of the last update on 2007-10-27.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.