2026 NPPES data Rheumatology Physician NPI 1306853239 MD
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Shawn Slack, MD

Rheumatology Physician in Everett, Washington. This profile is drawn from the federal National Provider Identifier Registry (CMS NPPES), which lists more than 7 million U.S. healthcare providers — including 6,181 in Rheumatology Physician, and covers specialty classification, practice address, and Medicare Part D prescribing data when reported. According to CMS, every field reflects the provider's official federal registration — see our methodology.

Federal data — no proprietary rating. We show these CMS records as-is — no composite score, no star rating, no editorial opinion layered on top.
Prescribing volume
2K
Medicare Part D claims · 341 beneficiaries · Rheumatology Physician avg: 2K
Compiled from official public sources by the PlainDoctor editorial team.

What the federal data shows

Shawn Slack, MD filed 2,061 Medicare Part D claims in 2023 as a Rheumatology Physician in Everett, Washington.

2K
Part D claims, 2023
Likely
board-certified (heuristic)

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.

Shawn Slack, MD's Medicare Part D volume vs every U.S. prescriber

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

2,061 Top 16% higher than 84% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). Below this entry. 400–600: 90,619 prescribers (7%). Below this entry. 600–800: 56,224 prescribers (4%). Below this entry. 800–1,000: 40,919 prescribers (3%). Below this entry. 1,000–1,200: 31,827 prescribers (2%). Below this entry. 1,200–1,400: 26,224 prescribers (2%). Below this entry. 1,400–1,600: 21,710 prescribers (2%). Below this entry. 1,600–1,800: 19,072 prescribers (1%). Below this entry. 1,800–2,000: 16,451 prescribers (1%). Below this entry. 2,000–2,200: 213,991 prescribers (16%). This entry sits in this band. 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 certification likely (heuristic — not verified)

Shawn Slack, MD practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation — signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).

What does the federal data show about Shawn Slack, MD?

Quality data not reported

NPI registry status

Active

Issued 08/02/2006

NPI 1306853239

Primary specialty

Rheumatology Physician

Mid-sized

6,181 US NPIs in this specialty

Medicare Part D claims

2,061 0% vs specialty avg

2023 prescription claims

Specialty avg: 2,054

Specialty distribution in Washington

How Rheumatology Physician compares to other specialties among Washington providers

Washington providers

Largest specialties in Washington (% of in-state providers)

Mental Health Counselor — 8.6%Mental Health Counselor8.6%Massage Therapist — 6.5%Massage Therapist6.5%Counselor — 5.7%Counselor5.7%Behavior Technician — 4.5%Behavior Technician4.5%Pharmacist — 4%Pharmacist4%Physical Therapist — 3.6%Physical Therapist3.6%Rheumatology Physician — 0.1%Rheumatology Physician0.1%
Largest specialties in Washington (% of in-state providers)

Specialty board-certification context

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

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

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

0%100%78%
Est. board-certified rate (Rheumatology 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).

Shawn Slack, MD appears in the CMS NPPES registry as a Rheumatology Physician provider holding MD credentials at 3901 HOYT AVE, Everett, WA, 98201, with a listed phone of (425) 259-0966. NPI 1306853239 was issued on 08/02/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what Slack 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 2,061 prescription claims written by this provider, covering 341 Medicare beneficiaries and totaling roughly $1.5 million 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.

Rheumatology Physician is a mid-sized specialty nationwide, with 6,181 enrolled providers across 52 states and an average of 2,054 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

3901 HOYT AVE
Everett, WA 98201

Provider Details

NPI 1306853239
Specialty Rheumatology Physician
Credentials MD
Gender Male
NPI Issued 08/02/2006

Hospital and facility affiliations

Facilities where Shawn Slack, MD bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" — a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.

Optum Care Washington PLLC
Bellevue, WA

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

License & disciplinary context — Washington WMC 2023 annual report

Aggregate state board data only — NOT a determination of any individual provider's status. The figures below describe statewide disciplinary activity across all ~34K Washington medical licensees in 2023 — they are NOT specific to Shawn Slack, MD. To verify Shawn Slack, MD's current license status, search the WMC public license lookup directly, or check the Federation of State Medical Boards (FSMB) verification service.

88
Total board actions, Washington 2023
Across 85 cases
2.59
Actions per 1,000 licensees
Washington statewide rate
probation
Most common action type
31 cases

WMC publishes annual disciplinary statistics as part of public-record reporting under each state's Administrative Procedure Act. See the full breakdown by action type and year on the Washington disciplinary trends page. Cross-checked against FSMB U.S. Medical Regulatory Trends.

Medicare Part D Prescribing Data

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

2,061
Total Claims
$1.5M
Total Drug Cost
341
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
4,475
Total Day Supply
131,905
Generic Drug Cost
$59K

Patient Demographics

Average Patient Age
74.5 years
Avg HCC Risk Score
2.02
Gender Split
72% female / 28% male
Age Distribution
<65: 24, 65-74: 149, 75-84: 131, 85+: 37

Top Prescribed Drugs (Medicare Part D)

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

What Shawn Slack, MD 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
Prednisone
431
Hydroxychloroquine Sulfate
334
Methotrexate
Methotrexate Sodium
273
Folic Acid
97
Alendronate Sodium
96
Allopurinol
70
Omeprazole
53
Gabapentin
47
Methylprednisolone
42
Mycophenolate Mofetil
42

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

Rheumatology Physician Overview

How Shawn Slack, MD fits within the Rheumatology Physician landscape nationally.

6,181
Rheumatology Physician Providers in US
52
States with Rheumatology Physician
2,054
Avg Claims per Provider

Shawn Slack, MD's 2,061 claims are above the specialty average of 2,054.

Nearby Rheumatology Physician Providers in Washington

Other clinicians with the same primary specialty enrolled in Washington, drawn from the same CMS NPPES roster as Slack.

Compare Rheumatology Physician nationally: see state-by-state distribution →

Before you book an appointment

Use this federal record as your verification checklist, not as a recommendation.

  • Confirm the NPI record is current in the official CMS registry — providers update their own NPPES details, and moves can lag. Verify this NPI
  • Check the active license and any disciplinary history with the Washington medical board — federal registration is not a license check. Credential verification guide
  • Weigh a second option: compare this provider with a nearby Rheumatology Physician peer on Medicare volume and prescribing patterns. Compare providers

Medicare Part D and MIPS figures describe practice patterns in federal programs only — they are not quality ratings, and PlainDoctor does not rate, rank, or recommend providers.

Frequently Asked Questions

What is Shawn Slack, MD's specialty?
Shawn Slack, MD specializes in Rheumatology Physician and practices in Everett, Washington. Credentials: MD.
How much does Shawn Slack, MD prescribe under Medicare Part D?
In 2023, Shawn Slack, MD wrote 2,061 Medicare Part D claims totaling $1.5M in drug costs for 341 beneficiaries.
Where is Shawn Slack, MD located?
Shawn Slack, MD is located at 3901 HOYT AVE, Everett, WA, 98201. Phone: (425) 259-0966.
What is Shawn Slack, MD's NPI number?
Shawn Slack, MD's National Provider Identifier (NPI) is 1306853239, issued on 08/02/2006.
How many Rheumatology Physician providers are there in the US?
There are 6,181 Rheumatology Physician providers across 52 states in the US. The average Rheumatology Physician provider writes 2,054 Medicare Part D claims per year.
What drugs does Shawn Slack, MD prescribe most often?
Based on 2023 Medicare Part D data, Shawn Slack, MD's most frequently prescribed drugs include Prednisone, Hydroxychloroquine Sulfate, Methotrexate. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does Shawn Slack, MD accept Medicare?
Shawn Slack, MD appears in CMS Medicare data with 2,061 Part D claims and 341 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify Shawn Slack, MD's credentials?
Shawn Slack, MD's NPI is 1306853239 with credentials MD. 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

Compiled from official public sources by the PlainDoctor editorial team.