2026 NPPES data General Practice Physician NPI 1518317692 M.D.
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ALFREDO AYALA DIAZ, M.D.

General Practice Physician in SAN JUAN, Puerto Rico. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.

Federal data — no proprietary rating. PlainDoctor publishes the actual CMS NPPES and Medicare records — NPI registration, specialty, practice location, and prescribing data — without a composite score or editorial opinion on top. Every field traces to a federal source.
Prescribing volume
166
Medicare Part D claims · 111 beneficiaries · General Practice Physician avg: 3K

What the federal data shows

ALFREDO AYALA DIAZ, M.D. filed 166 Medicare Part D claims in 2023 as a General Practice Physician in SAN JUAN, Puerto Rico.

166
Part D claims, 2023

Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) — no proprietary rating or editorial opinion is applied.

ALFREDO AYALA DIAZ, M.D.'s Medicare Part D volume vs every U.S. prescriber

Total Medicare Part D claims, 2023 — across all CMS prescribers nationally

166 35th percentile higher than 35% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). This entry sits in this band. 200–400: 182,923 prescribers (13%). Above this entry. 400–600: 90,619 prescribers (7%). Above this entry. 600–800: 56,224 prescribers (4%). Above this entry. 800–1,000: 40,919 prescribers (3%). Above this entry. 1,000–1,200: 31,827 prescribers (2%). Above this entry. 1,200–1,400: 26,224 prescribers (2%). Above this entry. 1,400–1,600: 21,710 prescribers (2%). Above this entry. 1,600–1,800: 19,072 prescribers (1%). Above this entry. 1,800–2,000: 16,451 prescribers (1%). Above this entry. 2,000–2,200: 213,991 prescribers (16%). Above this entry. This provider 0 2K+ every Part D prescriber (claims/yr), bucketed by value

Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source CMS Medicare Part D Prescriber Public Use File · 2023

Board-eligible specialty (heuristic — not verified)

ALFREDO AYALA DIAZ, M.D. practices in an ABMS-board-eligible specialty but we don't have enough CMS-participation signals to confirm active board-certified status. Consult CertificationMatters.org (the official ABMS public lookup).

What does the federal data show about ALFREDO AYALA DIAZ, M.D.?

Quality data not reported

NPI registry status

Active

Issued 06/20/2016

NPI 1518317692

Primary specialty

General Practice Physician

Mid-sized

16,677 US NPIs in this specialty

Medicare Part D claims

166 94% vs specialty avg

2023 prescription claims

Specialty avg: 2,872

Specialty distribution in Puerto Rico

How General Practice Physician compares to other specialties among Puerto Rico providers

Puerto Rico providers

General Practice Physician share within Puerto Rico

1. General Practice Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
General Practice Physician share within Puerto Rico

Specialty board-certification context

Estimated specialty board-certified rate — General Practice Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
General Practice Physician ABMS/AOA estimate

Est. board-certified rate (General Practice Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (General Practice Physician) — ABMS / AOA estimate

The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.

Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).

ALFREDO AYALA DIAZ, M.D. appears in the CMS NPPES registry as a General Practice Physician provider holding M.D. credentials at 150 JOSE DE DIEGO AVE, SAN JUAN, PR, 00907, with a listed phone of (787) 230-7557. NPI 1518317692 was issued on 06/20/2016. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what AYALA DIAZ most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 166 prescription claims written by this provider, covering 111 Medicare beneficiaries and totaling roughly $2K in drug spend. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

General Practice Physician is a mid-sized specialty nationwide, with 16,677 enrolled providers across 56 states and an average of 2,872 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist — always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.

Practice Address

150 JOSE DE DIEGO AVE
SAN JUAN, PR 00907

Provider Details

NPI 1518317692
Specialty General Practice Physician
Credentials M.D.
Gender Male
NPI Issued 06/20/2016

Medicare Part D Prescribing Data

CMS Medicare Part D prescriber-level data for calendar year 2023.

166
Total Claims
$2K
Total Drug Cost
111
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
170
Total Day Supply
1,531
Generic Drug Cost
$2K
Antibiotic Claims
47

Patient Demographics

Average Patient Age
72.2 years
Avg HCC Risk Score
1.70
Gender Split
68% female / 32% male
Age Distribution
<65: 19, 65-74: 46, 75-84: 30, 85+: 16

Top Prescribed Drugs (Medicare Part D)

Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.

What ALFREDO AYALA DIAZ, M.D. prescribes most

Top Medicare Part D drugs by claim count, 2023

claims
Source CMS Medicare Part D Prescriber Public Use File As of 2023
Drug Claims
Methylprednisolone
28
Famotidine
25
Pantoprazole Sodium
19
Azithromycin
13

* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.

General Practice Physician Overview

How ALFREDO AYALA DIAZ, M.D. fits within the General Practice Physician landscape nationally.

16,677
General Practice Physician Providers in US
56
States with General Practice Physician
2,872
Avg Claims per Provider

ALFREDO AYALA DIAZ, M.D.'s 166 claims are below the specialty average of 2,872.

Nearby General Practice Physician Providers in Puerto Rico

Other clinicians with the same primary specialty enrolled in Puerto Rico, drawn from the same CMS NPPES roster as AYALA DIAZ.

Compare General Practice Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is ALFREDO AYALA DIAZ, M.D.'s specialty?
ALFREDO AYALA DIAZ, M.D. specializes in General Practice Physician and practices in SAN JUAN, Puerto Rico. Credentials: M.D..
How much does ALFREDO AYALA DIAZ, M.D. prescribe under Medicare Part D?
In 2023, ALFREDO AYALA DIAZ, M.D. wrote 166 Medicare Part D claims totaling $2K in drug costs for 111 beneficiaries.
Where is ALFREDO AYALA DIAZ, M.D. located?
ALFREDO AYALA DIAZ, M.D. is located at 150 JOSE DE DIEGO AVE, SAN JUAN, PR, 00907. Phone: (787) 230-7557.
What is ALFREDO AYALA DIAZ, M.D.'s NPI number?
ALFREDO AYALA DIAZ, M.D.'s National Provider Identifier (NPI) is 1518317692, issued on 06/20/2016.
How many General Practice Physician providers are there in the US?
There are 16,677 General Practice Physician providers across 56 states in the US. The average General Practice Physician provider writes 2,872 Medicare Part D claims per year.
What drugs does ALFREDO AYALA DIAZ, M.D. prescribe most often?
Based on 2023 Medicare Part D data, ALFREDO AYALA DIAZ, M.D.'s most frequently prescribed drugs include Methylprednisolone, Famotidine, Pantoprazole Sodium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does ALFREDO AYALA DIAZ, M.D. accept Medicare?
ALFREDO AYALA DIAZ, M.D. appears in CMS Medicare data with 166 Part D claims and 111 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify ALFREDO AYALA DIAZ, M.D.'s credentials?
ALFREDO AYALA DIAZ, M.D.'s NPI is 1518317692 with credentials M.D.. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.

Data Sources

Provider Directory
CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
Specialty Classification
NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
Prescribing Data
CMS Medicare Part D Prescriber Public Use File (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
Limitations
Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.

See our complete data methodology for details on how we collect and process government data.

Data as of April 2026 (NPPES) / 2023 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).

Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology