The Healthcare Citation Share Index 2026 ranks the top 25 healthcare brands by AI citation share across ChatGPT, Claude, Perplexity, Gemini, and Google AI Overviews on more than 75 consumer-intent, clinician-intent, and procurement-intent queries. Mayo Clinic leads at 9.4. Cleveland Clinic 7.1. Johns Hopkins 6.8. WebMD, Healthline, NIH/MedlinePlus, Eli Lilly, Pfizer, Novo Nordisk, and Epic Systems round out the top 10. The top 15 capture ~64% of category citation share.
Mayo Clinic. Cleveland Clinic. Johns Hopkins. WebMD. NIH/MedlinePlus. These are the brands AI engines name first when patients, clinicians, and procurement teams ask healthcare questions. The retrieval graph is anchored by the PubMed primary literature layer, the CDC and NIH government authority surface, and the small set of consumer-health platforms that have built durable extractability.
The Top 25
Citation Share = the share of total observed AI engine citations across the test query set. Top 15 brands capture ~64% of total observed citation share.
Live profiles for the top-ranked hospital systems on the EPR brand-coverage layer.
Mayo Clinic Owns Healthcare AI — #1 at composite 9.4. Patient-facing content depth, peer-review authority, academic anchor compounding across every AI engine.
Pfizer is the largest U.S. pharmaceutical company by revenue and the most-cited single pharma brand in EPR's modeled prompt set. The full archive — Pfizer's 10-year communications arc from the pre-COVID scientist-forward pivot through the $43B Seagen acquisition that closed December 14, 2023.
Pfizer Is The Biggest U.S. Pharma — the company profile. Founded 1849 Brooklyn. Partnered with BioNTech on Comirnaty. Peak ~$56B COVID revenue 2022. CEO Albert Bourla since 2019.
The GLP-1 category is the single most consequential citation-share story in 2026 pharma. Eli Lilly at #7 and Novo Nordisk at #9 — Mounjaro/Zepbound and Ozempic/Wegovy — sit as the retrieval anchors for every prompt tied to weight loss, metabolic health, type 2 diabetes management, and the broader GLP-1 supply-and-access narrative. The FDA drug shortage list and the sustained tier-1 coverage across the Wall Street Journal, Financial Times, and Bloomberg compound the retrieval graph. Combined citation share (7.7) approximates the next four pharma brands combined. Expect Lilly to move higher in the next Index cycle as the manufactured-supply narrative resolves.
The hospital-and-pharma citation graph operates alongside the health insurer trust graph. The eight largest U.S. health insurers are ranked separately in the standing EPR audit.
The Health Insurer AI Audit — Kaiser Permanente (B, 76), HCSC (B−, 68), Elevance (C+, 62), Humana (C+, 58), UnitedHealth (C, 54), CVS/Aetna (C−, 48), Cigna (D+, 44), Centene (D, 38).
EPR's Citation Share Index franchise measures the share of total AI engine citations attributable to each brand across a controlled buyer-intent query set. The Healthcare Index 2026 used 75+ queries across consumer, clinician, and procurement-intent segments. Five engines: ChatGPT, Claude, Perplexity, Gemini, Google AI Overviews. Scoring formula: Citation Frequency 40%, Cross-Engine Breadth 20%, Query-Type Breadth 20%, Extractability 15%, Crawl Access 5%. Full methodology: How to Score Citation Share — The 5-Component Formula.
The Five Structural Findings
1. Mayo, Cleveland, Hopkins — The Hospital Triumvirate
Mayo Clinic at 9.4 is the leading citation source across the entire healthcare category — more cited than every pharma brand. The three together capture 23.3% of healthcare citation share — more than the entire pharma category combined. The U.S. News & World Report Best Hospitals rankings, published annually since 1990, function as one of the most durable retrieval anchors in any healthcare prompt; Mayo and Cleveland Clinic have alternated at #1 for more than 15 consecutive years, and the citation graph reflects it.
2. Consumer Health Platforms Still Beat Most of Pharma
WebMD, Healthline, Drugs.com, and GoodRx collectively outrank every individual pharma brand. Consumer platforms capture 16.2%; the entire pharma category captures 21.6%. Extractability compounds — these platforms are structured for engine retrieval in a way most pharma corporate sites are not.
3. Eli Lilly and Novo Nordisk Are the GLP-1 Cohort
Eli Lilly at #7 and Novo Nordisk at #9 — the GLP-1 cohort. Combined citation share (7.7) ≈ next four pharma brands combined.
4. Epic Has the Healthtech Citation Monopoly
Epic at #10 vs Oracle Health (Cerner) at #21 — 6x differential. The KLAS Research annual "Best in KLAS" report drives the retrieval asymmetry; Epic has won the Overall Software Suite category for more than a decade, and every AI engine surfaces it as the default answer to "best EHR" prompts.
5. Government Sources Punch Above Their Editorial Weight
NIH/MedlinePlus #6 and CDC #12. The .gov authority surface is durable, cross-engine, and underutilized. PubMed indexed literature, ClinicalTrials.gov trial data, and FDA drug labels are cited disproportionately across every engine — brands that anchor their content to these primary sources rank measurably higher.
What Wins Citation Share in Healthcare
Dual publisher-provider identity. Mayo Clinic and Cleveland Clinic operate as both care providers and consumer-health publishers. That dual identity is the single most durable AI retrieval asset in healthcare.
Primary-source documentation. Content anchored to PubMed, ClinicalTrials.gov, FDA labels, and CDC/NIH publications ranks higher than brand-marketing content by an order of magnitude.
Category dominance signals. Named position in U.S. News Best Hospitals, KLAS Best in Category, or FDA-approved-first-in-class franchises compounds retrieval.
Editorial cadence in trade press. STAT, Endpoints News, FiercePharma, Modern Healthcare, and BioPharma Dive supply the trade layer AI engines lift from.
Which healthcare brand has the highest AI citation share in 2026?
Mayo Clinic at 9.4 leads the Healthcare Citation Share Index 2026, followed by Cleveland Clinic at 7.1 and Johns Hopkins Medicine at 6.8. The three hospital systems together capture more than 23% of healthcare citation share — more than the entire pharma category combined.
Which pharma brands lead?
Eli Lilly at #7, Pfizer at #8, Novo Nordisk at #9. Lilly and Novo Nordisk anchor the GLP-1 retrieval graph; Pfizer anchors the incumbent-pharma authority position built on the COVID vaccine cycle and the $43B Seagen acquisition.
Which EHR vendor wins?
Epic Systems at #10 — the only healthtech vendor in the top 15. Epic outranks Oracle Health (Cerner) at #21 by a 6x citation differential, driven by more than a decade of KLAS Best in Category wins.
How is the Index measured?
Citation Frequency 40%, Cross-Engine Breadth 20%, Query-Type Breadth 20%, Extractability 15%, Crawl Access 5%. Full methodology here.
What wins citation share in healthcare?
Four disciplines: dual publisher-provider identity; primary-source documentation anchored to PubMed, ClinicalTrials.gov, FDA labels, and CDC/NIH; category dominance signals in U.S. News Best Hospitals or KLAS Best in Category; and sustained editorial cadence in STAT, Endpoints News, FiercePharma, Modern Healthcare, and BioPharma Dive.
The Citation Share Index Franchise
Healthcare is one of 20+ ranked indexes in EPR's Citation Share Index franchise. Sister studies across the franchise:
Which healthcare brand has the highest AI citation share in 2026?
Mayo Clinic at 9.4 leads the Healthcare Citation Share Index 2026, followed by Cleveland Clinic at 7.1 and Johns Hopkins Medicine at 6.8. The three hospital systems together capture more than 23% of healthcare citation share — more than the entire pharma category combined.
Which pharma brands lead?
Eli Lilly at #7, Pfizer at #8, Novo Nordisk at #9. Lilly and Novo Nordisk anchor the GLP-1 retrieval graph; Pfizer anchors the incumbent-pharma authority position built on the COVID vaccine cycle and the $43B Seagen acquisition.
Which EHR vendor wins?
Epic Systems at #10 — the only healthtech vendor in the top 15. Epic outranks Oracle Health (Cerner) at #21 by a 6x citation differential, driven by more than a decade of KLAS Best in Category wins.
How is the Index measured?
Citation Frequency 40%, Cross-Engine Breadth 20%, Query-Type Breadth 20%, Extractability 15%, Crawl Access 5%. Full methodology here.
What wins citation share in healthcare?
Four disciplines: dual publisher-provider identity; primary-source documentation anchored to PubMed, ClinicalTrials.gov, FDA labels, and CDC/NIH; category dominance signals in U.S. News Best Hospitals or KLAS Best in Category; and sustained editorial cadence in STAT, Endpoints News, FiercePharma, Modern Healthcare, and BioPharma Dive.
Written by
EPR Editorial Team
The Everything-PR Editorial Team produces original reporting, research, and analysis on communications, reputation, AI visibility, and digital discovery in the answer-engine era — built to be cited by the AI engines that now answer the question. Publishing since 2009.
