The 100 Most-Cited Websites in Google AI Mode for High-Stakes Health and Medical Consumer Decisions

LLM Authority Index Research | Google AI Mode | Health and Medical | July-September 2026

Google AI Mode uses a health and medical citation market that looks very different from its broad high-stakes source leaderboard.

LLM Authority Index analyzed 4,158 deduplicated Google AI Mode responses across 14 health and medical source verticals from July through September 2026. Those responses produced 26,141 visible citation events, 4,207 cited registrable domains, and 20,729 domain-response appearances under the same response-level counting framework used throughout the 2026 AI Citation Authority research series.

GoodRx ranked #1, appearing in 10.8% of responses. YouTube ranked #2 at 10.4%, Amazon #3 at 7.9%, NCOA #4 at 7.3%, and Healthline #5 at 6.6%.

The most important commercial result is not simply the order of the Top 100. It is how sharply the relevant source universe changes when Google AI Mode is restricted to health and medical consumer decisions. The health and medical Top 100 account for 42.7% of domain-response appearances, compared with 46.6% in the broad Google AI Mode high-stakes study. Yet only 28 domains appear in both Top 100 lists.

That means a broad AI Mode citation leaderboard can describe the platform while still being a poor earned-media map for a healthcare company.

The same health and medical slice is much closer to Google AI Overviews. The AI Mode and AI Overviews health Top 100s share 76 domains, or 61.3% Jaccard similarity at the domain-list level. The matched ChatGPT health Top 100 shares 41 domains with AI Mode.

This article is the intersection of the Health and Medical Citation Authority Study and the Google AI Mode Top 100 study.

Answer Capsule

Which websites are most frequently cited by Google AI Mode for high-stakes health and medical consumer decisions? In the LLM Authority Index July-September 2026 panel, GoodRx ranked #1 at 10.8% response citation coverage, YouTube #2 at 10.4%, Amazon #3 at 7.9%, NCOA #4 at 7.3%, and Healthline #5 at 6.6%. The study covers 4,158 deduplicated responses across 14 health and medical verticals. The Top 25 account for 24.2% of domain-response appearances, the Top 100 account for 42.7%, and 66 domains remained in the health and medical AI Mode Top 100 in all three months. Only 28 domains overlap with the broad Google AI Mode Top 100, while 76 domains overlap with the matched Google AI Overviews health Top 100.

Key Findings

• The raw archive contains 4,479 Google AI Mode observations assigned to the Health and Medical family from July through September 2026.
• 25 observations in this platform-category slice were explicitly marked as extraction failures.
• After the series' exact-repeat anti-double-counting rule, the eligible slice contains 4,158 deduplicated responses.
• Those responses contain 26,141 visible citation events, 4,207 cited registrable domains, and 20,729 domain-response appearances.
• GoodRx ranked #1 at 10.8% response coverage, followed by YouTube at 10.4%, Amazon at 7.9%, NCOA at 7.3%, and Healthline at 6.6%.
• The Top 10 account for 13.9% of domain-response appearances, the Top 25 for 24.2%, and the Top 100 for 42.7%.
• The health and medical AI Mode Top 100 shares 81 domains with the all-platform Health and Medical Top 100, but only 28 domains with the broad AI Mode Top 100.
• Google AI Mode and Google AI Overviews share 76 health and medical Top 100 domains. The matched ChatGPT health Top 100 shares 41 with AI Mode.
• 66 domains appeared in the Google AI Mode health and medical Top 100 in July, August and September.
• July and September shared 72 of 100 leading domains, or 56.3% Jaccard similarity.
• GoodRx appears across 13 of 14 source verticals. YouTube appears across all 14. Amazon appears across 11.
• Vertical leadership is highly specialized. American Addiction Centers leads Addiction Treatment Centers, Aspen Dental leads Dental Implants, NCOA leads Hearing Aids and Medical Alert Systems, Doctor On Demand leads Online Doctors, Amazon leads Online Pharmacies, Talkspace leads Online Therapy, and MyLabBox leads STD Tests.
• GoodRx appears in 10.8% of this health and medical AI Mode slice compared with 3.1% across AI Mode's broader high-stakes panel.
• Reddit moves in the opposite direction: 5.6% in this health and medical slice versus 14.2% across the broad AI Mode high-stakes panel.

Questions This Study Answers

• Which websites dominate Google AI Mode citations for high-stakes health and medical decisions, and how does that source hierarchy change by vertical?
• How persistent is the Google AI Mode health source market over time, and how portable is that authority to other AI platforms?
• What should health publishers, healthcare brands and CMOs measure before allocating resources to AI Mode-focused content, PR, partnerships or earned media?

Why This Research Belongs in Daily AI Search Marketing Decisions

This study is research-based, but its purpose is commercial decision support.

This Article combines two views of the same source market: the Google AI Mode platform view and the Health and Medical decision-family view.

For publishers and specialist sources, that makes it possible to describe measured AI citation visibility by platform, decision vertical and time rather than relying on a broad claim of AI authority.

For healthcare brands, CMOs, PR teams and agencies, the operating question is:

Which sources are already present around the exact health and medical consumer decisions our customers ask Google AI Mode to help them make?

Four findings matter for planning:

• the Top 100 account for 42.7% of response-level domain appearances in this AI Mode health and medical slice, compared with 46.6% across AI Mode's broader high-stakes source market;
• only 28 domains overlap between this Health and Medical Top 100 and the broad AI Mode Top 100;
• 66 domains remained in the monthly Health and Medical AI Mode Top 100 in July, August and September, and the median monthly Top 100 Jaccard similarity was 61.3%; and
• the final Health child-study Top 100 lists show AI Mode sharing 76 domains with Google AI Overviews, 54 with Gemini, 49 with Perplexity, 41 with ChatGPT and 38 with Microsoft Copilot.

The parent Health and Medical Citation Authority Study provides the category-level Persistence-Portability Gap interpretation. It reports 61.3% temporal persistence, 25.8% cross-platform portability, and an approximate 35.5 percentage-point Persistence-Portability Gap for Health and Medical decisions.

That category gap is exploratory. Article 25 should not create a separate AI Mode gap by subtracting its monthly persistence from one pairwise platform overlap because those statistics answer different questions.

Current outside research reinforces why platform, category and citation definition need to travel with every claim.

Ahrefs' September 2026 broad U.S. AI Mode study ranks Reddit first at 17.9% mention share, YouTube second at 17.8%, Google third at 12.5%, Facebook fourth at 10.2%, and Instagram fifth at 5.7%. This health-specific panel looks very different, with GoodRx #1, YouTube #2, Amazon #3, NCOA #4 and Healthline #5. Ahrefs Google AI Mode citation study

BrightEdge's healthcare research tracked ChatGPT, Google AI Mode and Google AI Overviews across 14 weeks and found that source type changes materially by engine and query intent. It also reported substantially greater healthcare citation volatility on Google than on ChatGPT. BrightEdge healthcare citation study

BrightEdge separately reports that google.com represented 44.9% of AI Mode citations in an August 2026 U.S. tracked set focused on consumer product and finance queries, versus 9.9% in AI Overviews. That is a different prompt population and metric from this article. BrightEdge AI Mode self-citation study

Tinuiti's Q3 2026 research reports more than 13x growth in google.com's share of AI Mode citations during 2026 and notes that Google increasingly cites its own surfaces, particularly in AI Mode. Tinuiti Q3 2026 AI Citation Trends Report

Those outside studies should not be merged numerically with this one. The useful agreement is structural: AI Mode source behavior changes with topic, source class, platform surface, prompt population and denominator.

Commercial Action Matrix: What Publishers and CMOs Can Do With the Findings

The daily operating model is therefore four-layered:

1. Current Google AI Mode health core: maintain the sources that matter now, with the collection date attached.
2. Vertical and decision-cluster layer: identify which sources dominate the exact consumer decision.
3. Longitudinal check: monitor whether priority sources persist, decline, rotate or change rank.
4. Cross-platform check: determine whether the same sources also matter in Google AI Overviews, ChatGPT, Gemini, Perplexity and Microsoft Copilot.

How This Study Fits the High-Stakes Consumer Decisions Research Corpus

This Article is the intersection of two parent studies:

• The Google AI Mode Platform Study
• The Health and Medical Citation Authority Study

It should also be read with:

• the 2026 AI Citation Authority Study;
• the Persistence-Portability Gap;
• Do AI Platforms Cite the Same Websites?;
• How Stable Are AI Citations?;
• Reddit's Decline in AI Citations for Health and Medical Decisions; and
• How Reddit Citations Changed in Google AI Mode for Health and Medical Decisions.

What We Studied

This analysis uses the frozen July through September 2026 LLM Authority Index parent corpus and restricts the analytical population to the Google AI Mode platform family and the Health and Medical research family.

Study size

The 14 source vertical labels are: Addiction Treatment Centers; Assisted Living Facilities; Dental Implants; Fertility Clinics; Hearing Aids; Home Health Care; IVF Clinics; Medical Alert Systems; Mental Health Treatment Centers; Online Doctors; Online Pharmacies; Online Therapy; STD Tests; and Weight Loss and Metabolic Health.

This section answers

• What denominator and primary ranking metric does this study use?
• How many Google AI Mode health and medical responses were analyzed?
• Which Health and Medical source verticals are included?

The 25 Most-Cited Websites in Google AI Mode for Health and Medical Decisions

The Top 25 show three different source roles operating at once:

• broad consumer-health publishers and navigation platforms, including GoodRx, Healthline and Everyday Health;
• commercial or provider-owned sources, including Amazon, Doctor On Demand, Sesame Care, Aspen Dental, Walgreens, Talkspace and PlushCare; and
• specialist authorities, including NCOA, HearingTracker, SeniorLiving.org and Consumer Reports.

GoodRx and YouTube are broad within the category. GoodRx appears across 13 source verticals and YouTube across all 14. By contrast, Aspen Dental and Affordable Dentures are highly concentrated in Dental Implants, while HearingTracker is concentrated in Hearing Aids.

The Full Top 100 Google AI Mode Health and Medical Citation Sources

The Health and Medical AI Mode Source Market Is More Diffuse Than AI Mode Overall

The health and medical market has a flatter head than AI Mode overall. Its Top 10 account for only 13.9% of all domain-response appearances, compared with 21.4% in the broad high-stakes AI Mode study.

The Top 100 gap is smaller, 42.7% versus 46.6%, because the health market still has many recurring mid-tier sources. The practical interpretation is that health and medical visibility is distributed across a large specialist ecosystem rather than dominated by a small handful of universal publishers.

That is especially important for PR planning. The commercially useful source market is not just the five domains at the top. Many specialist sources between ranks 20 and 100 have high response coverage inside one decision vertical.

Which Sources Gain the Most When the Analysis Is Restricted to Health and Medical Decisions?

Among domains that also appear in the broad Google AI Mode Top 100, several become far more important in the health and medical slice:

This is why a platform-wide source list can miss the most important earned-media targets for a specific health company.

Some specialists do not appear in the broad AI Mode Top 100 at all. Their category lift therefore cannot be calculated from the published broad Top 100, but their health-specific coverage is still measurable in this study.

The opposite pattern also matters. Forbes appears in 6.5% of the health slice versus 13.3% in broad AI Mode, and Reddit appears in 5.6% versus 14.2%. Broad authority does not translate uniformly into every high-stakes category.

The Most-Cited Sources by Individual Health and Medical Vertical

The differences are large enough that one health-wide target list would be strategically misleading.

• Addiction Treatment Centers is led by provider and institutional sources, with American Addiction Centers at 71.2% response coverage in this slice.
• Dental Implants is dominated by provider-owned and financing sources such as Aspen Dental, Affordable Dentures and CareCredit.
• Hearing Aids is led by NCOA and HearingTracker, with YouTube also prominent.
• Medical Alert Systems is led by NCOA, SafeHome and SeniorLiving.org.
• Online Doctors is led by Doctor On Demand, Sesame Care and PlushCare.
• Online Pharmacies is led by Amazon and GoodRx.
• Online Therapy is led by Talkspace, BetterHelp and Grow Therapy.
• STD Tests is led by MyLabBox and Everlywell.

The IVF Clinics label has only 52 eligible Google AI Mode responses in this slice and should be interpreted more cautiously than larger verticals. Fertility Clinics and IVF Clinics also overlap heavily as source labels.

Broad Publisher Authority and Specialist Authority Are Different Assets

A publisher can be commercially valuable in AI search without appearing near the top of a broad platform ranking.

GoodRx has both breadth and depth. It appears across 13 health and medical verticals and ranks #1 overall in the category.

YouTube has maximum category breadth, appearing across all 14 source verticals. Its #2 position reinforces that video is not an edge format in Google health answers. It is part of the citation landscape.

NCOA has narrower vertical breadth but extraordinary depth in Hearing Aids and Medical Alert Systems.

HearingTracker, Aspen Dental, Talkspace, MyLabBox and Doctor On Demand are examples of specialist authority. Their business value comes from repeatedly appearing in a particular decision market, not from being universal web publishers.

For publishers selling advertising or sponsorships, this suggests a more defensible sales story than a generic "AI authority" claim: document the exact high-intent prompt cluster where the site is repeatedly cited and report the denominator.

Google AI Mode Health Rankings Were Persistent at the Core, but Not Static

Across all three months, 66 domains remained in the Google AI Mode health and medical Top 100. The median of the three monthly Top 100 Jaccard comparisons was 61.3%.

The leading domains were fairly persistent even as their order moved:

• GoodRx moved #1 to #1 to #2.
• YouTube moved #3 to #2 to #1.
• Amazon moved #2 to #4 to #5.
• NCOA moved #11 to #3 to #3.
• Healthline moved #4 to #5 to #6.
• Forbes moved #6 to #7 to #4.
• Reddit moved #7 to #6 to #7.

The July-to-September Top 100 Jaccard similarity was 56.3%. That is meaningful continuity, but it still means 28 of the July Top 100 domains were outside the September Top 100.

This aggregate persistence should not be confused with same-prompt citation stability. The separate citation drift study found much higher turnover when the unit is the exact repeated prompt-platform scenario.

Google AI Mode Health Sources Are Related to, but Not Interchangeable With, Other AI Platforms

The final Health and Medical child-study Top 100 lists show a substantial Google-to-Google core and much lower overlap with several other engines.

The Google-to-Google similarity is much stronger than AI Mode's overlap with ChatGPT, Perplexity or Copilot. At the same time, only 28 domains overlap with AI Mode's broad high-stakes Top 100.

That combination is commercially important. Category can matter more than platform-wide reputation, and platform still matters inside the category.

The two Google health lists also have very similar leaders:

These percentages do not establish identical retrieval behavior or identical cited pages. They show that many of the same organizations recur after aggregating to registrable domains across the same commercial Health and Medical decision family.

For planning, maintain three layers: a cross-platform health core, an AI Mode-specific source layer, and a vertical-specific specialist layer.

How This Study Relates to Other Health and AI Search Research

BrightEdge: healthcare source types differ by engine and query type

BrightEdge tracked healthcare citations across ChatGPT, Google AI Mode and Google AI Overviews for 14 weeks from October 2025 through January 2026. Its study categorized source types and query intents rather than publishing a commercial domain Top 100. BrightEdge reported that Google AI Mode used a broader "other" source mix than ChatGPT for definition and treatment queries, and it measured materially higher week-to-week citation volatility on Google than on ChatGPT. (BrightEdge healthcare citation study)

LLMAI's result is compatible with that broader-source observation. The Google AI Mode health Top 100 captures only 42.7% of domain-response appearances, and the Top 10 capture just 13.9%, indicating a long source tail in this commercial decision panel.

The studies should not be numerically compared as if they measure the same thing. BrightEdge classified source types and weekly volatility. LLMAI ranks registrable domains by response citation coverage across 14 commercial health decision verticals.

Ahrefs: broad AI Mode rankings are dominated by a different source mix

Ahrefs' September 2026 all-topic AI Mode ranking reports Reddit, YouTube, Google, Facebook and Instagram as its leading domains under a mention-share methodology. (Ahrefs AI Mode Top 50)

LLMAI's health-specific result is very different: GoodRx ranks #1, Amazon #3, NCOA #4 and Healthline #5. Only 28 domains overlap between LLMAI's health Top 100 and its own broad high-stakes AI Mode Top 100.

That difference is not evidence that one study is wrong. The prompt population, ranking metric, denominator, time period and topic mix are different. It is evidence that broad platform rankings should not be treated as universal category maps.

Ahrefs: AI Mode and AI Overviews can reach similar answers through different citations

An Ahrefs study of 730,000 paired responses reported high semantic similarity between AI Mode and AI Overviews but low citation-level overlap. (Ahrefs AI Mode vs. AI Overviews study)

LLMAI finds 76 shared registrable domains between the two Google health Top 100 lists. These findings can coexist because the unit is different. Ahrefs examined citation overlap at the response and source level across a broad query set, while this article compares aggregated Top 100 domain lists inside a single high-stakes category.

BrightEdge: AI Mode self-citation depends on the product surface and category

BrightEdge reported that google.com represented 44.9% of AI Mode citations in an August 2026 tracked set focused on consumer product and finance queries, and noted that healthcare has thinner rich-result module coverage. (BrightEdge AI Mode self-citation study)

In LLMAI's health and medical panel, google.com ranks #18 at 3.4% response citation coverage. Those numbers are not directly comparable. BrightEdge reports share of citation events in a different prompt population, while LLMAI reports the share of responses citing a registrable domain at least once.

The useful lesson is methodological: AI Mode source behavior can change materially by category and by what the collection system counts as a citation surface.

Conductor: broad healthcare benchmarks surface a more institutional source set

Conductor's 2026 Health Care AEO/GEO benchmark identifies Mayo Clinic, Cleveland Clinic, Healthline, GoodRx and WebMD as leading domains across a much broader health care AI visibility dataset. (Conductor health care benchmarks)

LLMAI's commercial health decision panel moves GoodRx to #1 and elevates marketplaces, provider-owned comparison sources, nonprofits and specialist publishers. The difference follows directly from the prompt design: hearing aids, dental implants, online doctors, online pharmacies, therapy and medical alert systems are commercial decision markets, not a generic sample of health information queries.

Tinuiti: category and source-type shifts are visible across AI platforms

Tinuiti's Q3 2026 AI Citation Trends Report tracks multiple product categories including OTC health and reports continuing changes in social, ecommerce and google.com citation share across major AI platforms. (Tinuiti Q3 2026 AI Citation Trends Report)

LLMAI addresses a different question: which registrable domains repeatedly appear in high-stakes commercial health decisions, and which ones matter specifically on AI Mode.

How the LLM Authority Index Study Is Different

This study is not positioned as the largest healthcare or AI Mode citation dataset. Larger providers operate broader cross-industry indexes.

The defensible distinction is the combination of:

• one defined platform family: Google AI Mode;
• one high-stakes commercial decision family: Health and Medical;
• 14 explicitly enumerated source vertical labels;
• three monthly measurement periods;
• response-level registrable-domain citation coverage as the primary metric;
• visible citation events as a secondary metric;
• exact-repeat anti-double-counting across overlapping source exports;
• Public Suffix List registrable-domain consolidation;
• explicit extraction-failure accounting;
• comparison against the all-platform Health and Medical ranking, broad AI Mode ranking and matched Google AI Overviews health ranking; and
• commercial interpretation for publishers, healthcare brands and CMOs.

Why AI Citation Studies Can Disagree

Two AI Mode healthcare studies can produce different rankings without either one being methodologically invalid.

1. Prompt intent. Disease definitions, symptoms, treatments, "best" comparisons, pricing and provider-selection questions surface different source classes.
2. Vertical mix. Hearing aids, dental implants, fertility clinics, online pharmacies and addiction treatment centers do not share the same source ecosystem.
3. Platform surface. Google AI Mode and Google AI Overviews are related products but expose different answer and citation contracts.
4. Time window. Source selection can move meaningfully across weeks or months.
5. Metric. Response coverage, raw citation share, unique URLs, unique domains, mention share and referral traffic answer different questions.
6. Domain normalization. Subdomains and country-specific hosts may be consolidated differently.
7. Prompt geography. Health services, pharmacies and provider options are often location-sensitive.
8. Infrastructure and rich-result handling. A collector may record a Google module, redirect, map or underlying publisher in different ways.
9. Duplicate handling. Overlapping exports or repeated prompt records can overweight a source if not deduplicated consistently.
10. Commercial versus clinical prompt design. A study designed around clinical information will tend to surface a different source universe than a study designed around consumer decisions.

For this reason, LLMAI publishes the denominator, vertical composition and counting rules alongside the ranking.

What the Results Mean for Health and Medical Publishers

1. Prove the exact commercial footprint

A health publisher should report where it is cited, for which decision clusters, on which platform, and across what denominator. "Visible in AI" is too broad to be useful.

2. Separate breadth from specialist depth

GoodRx and YouTube have broad category reach. HearingTracker, SafeHome, Talkspace, MyLabBox and many provider-owned sites have concentrated strength in specific decisions. Both can be commercially valuable.

3. Treat AI Mode and AI Overviews as related but separate inventory

The two Google surfaces share 76 of their health Top 100 domains, but 24 domains differ on each list. Publishers should measure both instead of assuming one Google citation report covers the other.

4. Preserve pages that repeatedly earn citations

The domain ranking is only the first layer. Publishers should identify the specific cited URLs, keep them current, preserve stable URLs when possible and track page-level citation drift.

5. Use independent citation data carefully in sales materials

A publisher can accurately say a site appears in a defined share of tracked AI Mode responses. It should not convert that visibility statistic into a claim that Google medically endorses the publisher.

What the Results Mean for Healthcare CMOs and Brands

Start with the exact commercial prompt cluster

A company selling hearing aids should begin with Hearing Aids prompts, not a broad healthcare source list. An online pharmacy should begin with Online Pharmacies. The relevant source maps are different.

Identify recurring third-party sources

For each prompt cluster, separate first-party citations from recurring independent domains. Those recurring third parties are the clearest earned-media candidates.

Measure Google surfaces separately

A source can be strong in both AI Mode and AI Overviews, but the two products are not identical. Baseline both surfaces before outreach or content changes.

Track citations and recommendations separately

A domain can be cited without the associated company being recommended, and a company can be mentioned without its own domain being cited. These are separate visibility signals.

Re-run the benchmark after material changes

The monthly Top 100 has a stable core but meaningful turnover. A campaign should be evaluated with matched prompts and repeated measurement rather than a one-time screenshot.

Avoid turning citation visibility into a clinical-quality claim

Citation frequency is a search visibility metric. It is not a medical safety score, quality rating or endorsement.

Methodology

Parent dataset

The parent LLM Authority Index corpus covers July, August and September 2026 observations across six AI platform families and 53 source vertical labels. The flagship study analyzes 60,881 deduplicated responses and 278,499 visible citation events after frozen eligibility and anti-double-counting rules.

Platform and category restriction

This article restricts the frozen corpus to observations assigned to:

• Platform family: Google AI Mode
• Research family: Health and Medical
• Months: July, August and September 2026

Explicit extraction failures

Observations whose archived extraction metadata explicitly marked the response as an extraction failure were excluded before ranking. This platform-category slice contains 25 explicit failures.

Exact-repeat anti-double-counting

For analytical anti-double-counting, LLMAI retains one record when multiple source records in the slice have the same:

• report month;
• exact raw platform/source surface;
• normalized prompt text; and
• exact set of original citation URLs.

This rule is intended to prevent overlapping source exports from double-counting identical captured responses. It is not a claim that an underlying prompt was executed only once.

Prompt normalization

Prompt text is normalized with Unicode NFKC normalization, case folding, whitespace collapse and trimming for the exact-repeat key.

Domain normalization

Citation URLs are parsed to hostnames, lowercased, stripped of www., and consolidated to the registrable domain using the Public Suffix List. For example, pharmacy.amazon.com consolidates to amazon.com.

Public infrastructure handling

The research series distinguishes publisher domains from obvious navigation or technical infrastructure when a platform exposes those artifacts. No additional infrastructure domains were removed from this specific public Top 100 under the frozen category-slice rule set. The raw URL archive remains available for auditability.

Primary ranking metric: Response Citation Coverage

For a domain d:

Response Citation Coverage(d) = eligible responses citing d / all eligible responses in the slice

A domain counts at most once per response for the primary metric, even if multiple URLs from that domain appear in one response.

Secondary metric: visible citation events

Visible citation events are retained as a secondary metric. They show citation depth and repeated links but are not the primary ranking measure because platforms expose different citation densities.

Vertical membership

The vertical labels originate from the source datasets. They should not be interpreted as 14 statistically independent clinical industries. Fertility Clinics and IVF Clinics overlap heavily, Home Health Care contains some employment/franchise-adjacent prompts, and Medical Alert Systems has no July source dataset in the frozen panel.

Monthly persistence

A domain is counted as persistent when it appears in that month's Top 100. Pairwise overlap is reported both as shared-domain count and Jaccard similarity.

Category lift

Category lift compares response citation coverage in this Health and Medical AI Mode slice with the domain's response coverage in the published broad Google AI Mode high-stakes study when that domain is present in the broad Top 100.

Limitations

• This is a defined high-stakes consumer-decision prompt population, not a random sample of all health questions on Google AI Mode.
• The study measures visible citations captured in the archived response data, not Google's internal retrieval process.
• Citation does not prove endorsement, recommendation, medical quality, safety or causal influence.
• The 14 source vertical labels have unequal response counts.
• Some verticals are much more commercial than clinical.
• Fertility Clinics and IVF Clinics overlap heavily.
• Home Health Care includes some franchise and employment-adjacent intent.
• Medical Alert Systems lacks a July source dataset.
• IVF Clinics has a relatively small eligible AI Mode denominator in this slice.
• Results may differ by geography, account state, language, query wording, rollout state and collection method.
• A domain-level ranking can hide substantial URL-level churn.
• Cross-study percentage comparisons can be invalid when the underlying metrics differ.
• This study does not evaluate the clinical accuracy of cited pages.

Commercial Relationship Disclosure

LLM Authority Index is part of a business ecosystem that provides AI visibility, research, and marketing services. Affiliated businesses may have current or historical commercial relationships with companies or publishers that appear in the dataset. Commercial relationships are not inputs to ranking methodology. Domains are included based on observed citation data. A ranking is not an endorsement. The presence or absence of a commercial relationship should not be interpreted as the cause of a result.

References

1. LLM Authority Index: The 2026 AI Citation Authority Study
2. LLM Authority Index: The Most-Cited Websites in AI for High-Stakes Health and Medical Consumer Decisions
3. LLM Authority Index: The 100 Most-Cited Websites in Google AI Mode for High-Stakes Consumer Decisions
4. LLM Authority Index: The 100 Most-Cited Websites in Google AI Overviews for High-Stakes Health and Medical Consumer Decisions
5. LLM Authority Index: Do AI Platforms Cite the Same Websites?
6. LLM Authority Index: How Stable Are AI Citations?
7. BrightEdge: Healthcare AI Citations Across ChatGPT and Google
8. BrightEdge: Google AI Mode Cites Itself More Than AI Overviews
9. Ahrefs: The 50 Most-Cited Websites in Google AI Mode
10. Ahrefs: Are AI Mode and AI Overviews Just Different Versions of the Same Answer?
11. Conductor: Health Care Industry 2026 AEO / GEO Benchmarks
12. Tinuiti: Q3 2026 AI Citation Trends Report

Related LLM Authority Index Research

Parent studies and measurement framework

• The 2026 AI Citation Authority Study
• The Health and Medical Citation Authority Study
• The Google AI Mode Platform Study
• The Persistence-Portability Gap
• Do AI Platforms Cite the Same Websites?
• How Stable Are AI Citations?

Sibling Health and Medical platform studies

• Google AI Overviews
• ChatGPT
• Perplexity
• Gemini
• Microsoft Copilot

Health and Medical Reddit trend studies

• Health and Medical Reddit parent study
• Google AI Overviews Reddit trend
• Google AI Mode Reddit trend
• ChatGPT Reddit trend
• Perplexity Reddit trend
• Gemini Reddit trend
• Microsoft Copilot Reddit trend