How Reddit Citations Changed in Google AI Overviews for High-Stakes Health and Medical Consumer Decisions

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

Reddit remained a visible source in Google AI Overviews for high-stakes health and medical questions from July through September 2026, but its citation footprint weakened over the quarter.

On the balanced 13-vertical July-to-September endpoint, Reddit citation-event share fell from 1.64% to 1.27%, a 22.2% relative decline. Reddit response citation coverage fell from 6.23% to 4.90%, down 21.2%.

The full three-month platform slice shows the same direction. Reddit response coverage moved from 6.23% in July to 6.19% in August and 5.09% in September, while Reddit's rank moved from #4 to #5 to #8.

The strict matched-prompt result is negative but less one-sided than in ChatGPT. Among 548 matched Google AI Overviews scenarios, Reddit remained cited in 24, disappeared in 25, newly appeared in 15, and was absent in 484. Matched coverage fell from 8.94% to 7.12%.

Answer Capsule

Reddit citation visibility declined in Google AI Overviews for high-stakes health and medical consumer decisions from July to September 2026, but the decline was much milder than the near-collapse observed in ChatGPT. In the balanced 13-vertical endpoint, Reddit citation-event share fell 22.2%, from 1.64% to 1.27%, while response citation coverage fell 21.2%, from 6.23% to 4.90%. In the strict matched panel, 548 scenarios were paired: Reddit remained cited in 24, disappeared in 25, newly appeared in 15, and was absent in 484. The exact two-sided McNemar p-value is approximately 0.154, so the loss-gain imbalance is directionally negative but not statistically significant at the conventional 0.05 threshold.

Key Findings

• Reddit ranked #4 in July, #5 in August and #8 in September by Google AI Overviews response citation coverage in the full health and medical platform slice.
• Full-panel response coverage moved from 6.23% to 6.19% to 5.09%.
• Full-panel Reddit citation-event share moved from 1.64% to 1.50% to 1.31%.
• On the balanced 13-vertical endpoint, Reddit event share fell from 1.64% to 1.27%, down 22.2%.
• Balanced response citation coverage fell from 6.23% to 4.90%, down 21.2%.
• The strict matched set contained 548 scenarios: 24 both, 25 losses, 15 gains, and 484 neither.
• Matched response coverage fell from 8.94% to 7.12%, down 20.4%.
• Reddit losses outnumbered gains 25 to 15, a 1.67-to-1 imbalance.
• The exact two-sided McNemar test gives p ≈ 0.154, so this matched imbalance is not statistically significant at the 0.05 level.
• In the fresh 13-vertical platform audit, 9 of 10 verticals with measurable July Reddit event share declined.
• 8 of those 10 measurable verticals declined in response coverage.
• The largest event-share declines were Dental Implants (-47.7%), STD Tests (-47.4%), Hearing Aids (-38.0%), IVF Clinics (-32.0%), and Weight Loss and Metabolic Health (-28.5%).
• Home Health Care increased from a very low July baseline, with Reddit event share rising from 0.97% to 2.94%.
• Online Doctors had lower Reddit event share but higher response coverage, another example of why both metrics should be reported separately.
• No single publisher replaced Reddit in the 25 matched loss scenarios. Talkspace newly appeared in 16.0%; Facebook, Forbes, InstaCured and BetterHelp each appeared in 12.0%.

Questions This Study Answers

• How much did Reddit citation visibility change in Google AI Overviews for high-stakes health and medical decisions from July to September 2026?
• Does the decline remain when the same prompt and Google AI Overviews surface are paired?
• Which health and medical verticals and replacement sources changed most as Reddit visibility fell?

Why This Research Belongs in Daily AI Search Marketing Decisions

Article 52 isolates one source, Reddit, inside one surface, Google AI Overviews, and one commercial decision family, Health and Medical. That narrow design makes the study useful for day-to-day AI search marketing because it separates measurements that are often collapsed into one visibility score:

1. Where does Reddit rank inside the Google AI Overviews health source market?
2. How often is Reddit actually cited, measured both as citation-event share and response citation coverage?
3. Does the same prompt-plus-surface scenario keep or lose Reddit over time?

In the three-month Google AI Overviews Health and Medical source study, Reddit still ranked #5 overall at 5.82% response citation coverage. That aggregate position can coexist with current-period weakening: Reddit ranked #4 in July, #5 in August and #8 in September, while full-panel response coverage moved from 6.23% to 6.19% to 5.09% and citation-event share moved from 1.64% to 1.50% to 1.31%.

The balanced 13-vertical endpoint points in the same direction. Reddit citation-event share fell 22.2%, from 1.64% to 1.27%, while response citation coverage fell 21.2%, from 6.23% to 4.90%. In the locked matched set, 25 scenarios lost Reddit while 15 gained it, a 1.67-to-1 loss-to-gain ratio, and matched coverage fell from 8.94% to 7.12%, about a 20.4% decline.

The matched result requires careful interpretation. The exact two-sided McNemar test is p ≈ 0.154, so the loss-gain imbalance is directionally negative but does not meet the conventional 0.05 significance threshold in this sample. Publishers and healthcare marketers can responsibly describe the observed decline, but should not present the matched test as statistically significant evidence of a structural Google change.

For publishers, a three-month aggregate rank should not be sold as proof that current visibility is stable. For healthcare brands and CMOs, source strategy should be monitored with a fixed prompt panel, a defined platform surface, and separate rank, coverage, event-share, and matched-loss metrics.

The vertical audit strengthens the need for segmentation. Among the 10 balanced verticals with measurable July Reddit event share, 9 declined, while 8 of those 10 declined in response coverage. Dental Implants fell 47.7% in event share, STD Tests 47.4%, Hearing Aids 38.0%, IVF Clinics 32.0%, and Weight Loss and Metabolic Health 28.5%. Home Health Care moved sharply higher from a very low baseline, and Online Doctors lost event share while gaining response coverage. Those exceptions show why category averages and a single citation metric are not enough for operating decisions.

The matched platform comparison is equally important. In the parent Health and Medical study, ChatGPT matched Reddit coverage fell 96.8%, Perplexity 100.0% on a much smaller base, Google AI Overviews 20.4%, Google AI Mode 20.0%, and Gemini 40.0%. Microsoft Copilot had no captured Reddit citations at either matched endpoint. One blended 'Reddit visibility in AI' score would hide those differences.

This result also belongs inside the broader Health and Medical Citation Authority Study. That study reports 61.3% median monthly Top 100 persistence, 25.8% median cross-platform Top 100 portability, and an approximate 35.5 percentage-point Persistence-Portability Gap. It also reports 20 domains appearing in all six platform Top 100 lists, out of 290 distinct domains in the combined six-platform Top 100 union.

The Google AI Overviews Health source market is somewhat more persistent within its own surface: 69 domains remained in the monthly Top 100 across July, August and September, and median monthly Top 100 Jaccard similarity was 65.3%. The final Health child-study Top 100 lists show Google AI Overviews sharing 76 domains with Google AI Mode, 52 with Gemini, 50 with Perplexity, 41 with Microsoft Copilot and 39 with ChatGPT.

Those are useful context measures, but Article 52 should not subtract one pairwise platform overlap from one temporal persistence statistic to manufacture a separate Persistence-Portability Gap. The comparison structures are different. The Persistence-Portability Gap framework is most useful here as a category-level interpretation: source authority can be more durable over time than transferable across engines, while an individual source can still weaken inside a relatively persistent platform-category market.

Health and Medical research also needs an additional guardrail. Citation visibility is separate from clinical quality, medical accuracy, safety, endorsement, brand mentions, recommendation rate, rank, sentiment, citation-recommendation coupling, and downstream business outcomes. This study measures the visible source layer around commercial high-stakes health decisions. It does not rank clinical truth or establish that a cited source caused a healthcare recommendation.

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

Where Article 52 Fits in the High-Stakes Consumer Decisions Corpus

Article 52 is a child analysis of two parent studies:

• the Health and Medical Reddit decline study, which provides the balanced family endpoint and matched platform comparison; and
• the Google AI Overviews Health and Medical source study, which provides the surrounding three-month AIO source market, including Reddit's #5 aggregate rank and 5.82% response coverage, 69 domains present in all three monthly Top 100s, and 65.3% median monthly Top 100 persistence.

The platform-level context comes from the overall Google AI Overviews Top 100 study. The broader interpretation comes from the 2026 AI Citation Authority Study, the overall Reddit decline study, the cross-platform citation-overlap study, the citation-drift study, and the Persistence-Portability Gap framework. Those studies answer different questions and should not be collapsed into one visibility score.

What We Studied

This article is the Google AI Overviews platform-specific extension of the broader LLM Authority Index study, Reddit's Decline in AI Citations for High-Stakes Health and Medical Consumer Decisions.

The underlying Google AI Overviews Health and Medical source study contains:

The 14 source vertical labels are:

1. Addiction Treatment Centers
2. Assisted Living Facilities
3. Dental Implants
4. Fertility Clinics
5. Hearing Aids
6. Home Health Care
7. IVF Clinics
8. Medical Alert Systems
9. Mental Health Treatment Centers
10. Online Doctors
11. Online Pharmacies
12. Online Therapy
13. STD Tests
14. Weight Loss and Metabolic Health

Medical Alert Systems has no July source dataset in the frozen archive. It is included in the three-month source study, but it is excluded from the balanced July-to-September endpoint. The remaining 13 verticals have observations at both endpoints.

The Core Finding: Reddit Declined on the Balanced Google AI Overviews Health Endpoint

Questions This Section Answers

• Did Reddit lose both event share and response coverage?
• How large was the Google AI Overviews decline?
• Was the decline smaller than the all-platform Health and Medical decline?

Yes. Both metrics declined on the balanced 13-vertical endpoint.

The broader all-platform Health and Medical parent study reported a 53.5% decline in Reddit citation-event share across the balanced family panel. Google AI Overviews declined much less sharply than that family aggregate because ChatGPT and Perplexity experienced substantially larger losses.

This child study therefore shows weakening, not disappearance. Reddit remained a visible Google AI Overviews source in September, even as its share, coverage and rank moved lower.

Reddit Fell Across the Full Three-Month Google AI Overviews Health Panel

Questions This Section Answers

• Was September an isolated decline or part of a three-month pattern?
• Did Reddit lose rank as its coverage fell?
• How does the full monthly panel differ from the balanced endpoint?

The full monthly platform slice trends lower:

The full monthly panel includes Medical Alert Systems in September, while the balanced endpoint removes that September-only vertical so July and September are compared across the same 13 verticals.

The monthly pattern is gradual. Coverage was almost flat from July to August, then fell by roughly 1.1 percentage points from August to September. Rank moved more visibly, from #4 to #5 to #8, showing that other sources gained relative position even before Reddit disappeared from the source market.

The Strict Matched-Prompt Test Is Negative but Less One-Sided Than ChatGPT

Questions This Section Answers

• Did Reddit decline when prompt wording and platform surface were held constant?
• How many matched scenarios lost Reddit compared with gains?
• Was the loss-gain imbalance statistically significant?

The locked Article 30 Google AI Overviews matched panel contains 548 scenarios:

Reddit losses outnumbered gains 25 to 15, a 1.67-to-1 imbalance.

Matched response coverage fell from 8.94% to 7.12%, a 20.4% relative decline.

The exact two-sided McNemar test gives p ≈ 0.154. That means the matched Google AI Overviews loss-gain imbalance is directionally negative, but it does not meet the conventional 0.05 threshold for statistical significance inside this sample.

This is an important contrast with the ChatGPT financial and insurance child studies, where the matched loss-gain imbalance was much larger and statistically stronger. It also shows why a directional endpoint decline and a matched statistical test answer different questions.

The Platform-Specific Vertical Audit Shows Broad but Uneven Decline

Questions This Section Answers

• Did every health and medical vertical decline inside Google AI Overviews?
• Which topics had the largest Reddit losses?
• Which topics moved against the category-wide trend?

The Google AI Overviews vertical audit is broad but not uniform.

Among the 10 balanced verticals with measurable July Reddit event share, 9 declined and one increased. On response coverage, 8 declined and 2 increased.

The steepest event-share declines were:

1. Dental Implants: down 47.7%.
2. STD Tests: down 47.4%.
3. Hearing Aids: down 38.0%.
4. IVF Clinics: down 32.0%.
5. Weight Loss and Metabolic Health: down 28.5%.

Home Health Care moved sharply against the trend, but from a very low base: Reddit event share rose from 0.97% to 2.94%, and response coverage rose from 1.11% to 2.94%.

Online Doctors also demonstrates why event share and coverage should be separated. Event share fell from 1.72% to 1.48%, while response coverage rose from 6.92% to 7.69%.

Medical Alert Systems is not assigned a July zero. The frozen archive has no July source dataset for that vertical, so the missing month remains missing.

What Appeared When Reddit Disappeared?

Questions This Section Answers

• Did one source consistently replace Reddit?
• Which domains appeared most often in matched Reddit-loss scenarios?
• Does the evidence support a single replacement-source strategy?

No single source consistently replaced Reddit across the 25 matched Google AI Overviews scenarios where Reddit appeared in July but not September.

Talkspace was the most common newly appearing domain, but it appeared in only 16.0% of Reddit-loss scenarios. Several other domains appeared in only 12.0% or 8.0%.

The replacement mix spans therapy platforms, broad publishers, provider sites, social platforms, hearing specialists and telehealth brands. That is evidence of source redistribution, not a one-for-one replacement.

For health brands, the practical implication is that a Reddit decline does not create one obvious publisher target. The stronger strategy is to identify recurring source classes inside each high-intent prompt cluster.

Platform Differences: Google AI Overviews Was Much More Stable Than ChatGPT

Questions This Section Answers

• Was the Reddit decline similar across AI platforms?
• How did Google AI Overviews compare with ChatGPT and Google AI Mode?
• Why should health teams report source visibility by platform?

The parent Health and Medical matched panel shows large platform differences:

Google AI Overviews and Google AI Mode were far more stable than ChatGPT in the matched health panel. ChatGPT recorded 30 losses and zero gains, while Google AI Overviews recorded 25 losses and 15 gains.

A single blended Reddit visibility KPI would hide that difference. Healthcare brands, publishers, clinics, telehealth companies and consumer-health platforms should treat platform as a first-class reporting dimension.

What This Means for Health and Medical Brands and CMOs

Questions This Section Answers

• Should health brands stop investing in Reddit?
• What should replace a single-source authority strategy?
• Which metrics should CMOs track next?

1. Do not treat Reddit as a fixed AI citation channel

Reddit remained visible in Google AI Overviews, but both balanced event share and response coverage declined. Source visibility should be treated as dynamic.

2. Track Google separately from ChatGPT

The Google AI Overviews matched decline was about 20%, while ChatGPT's matched health coverage fell almost 97%. A blended AI-source KPI would conceal a major platform difference.

3. Build a diversified third-party authority portfolio

Matched Reddit-loss scenarios redistributed across therapy platforms, publishers, provider sites, social sources, hearing specialists and telehealth brands. That argues for diversification rather than one replacement target.

4. Separate citations from recommendations

Visible citation does not prove that a source caused a brand mention, recommendation or ranking. Track citations, brand mentions, recommendation rate, comparison placement, sentiment and company-owned visibility separately.

5. Manage at the vertical and prompt-cluster level

Dental Implants, Hearing Aids, STD Tests, Online Therapy and Home Health Care moved very differently. Measurement and outreach should follow the commercial prompt clusters that matter to the business rather than one health-wide average.

What This Means for Health and Medical Publishers

Reddit's decline creates possible source-market opportunity, but not automatic transfer.

A publisher can use this research to identify where Google AI Overviews is changing its source mix and where editorial, comparison, research or educational content may have room to gain visibility. The source-change data does not imply that any one content format guarantees citation.

For publishers selling advertising, research, sponsorship or data partnerships, a defensible commercial story can focus on:

• which health verticals cite the publisher;
• which high-intent prompt clusters produce citations;
• how visibility changes month to month;
• whether the publisher appears in Reddit-loss scenarios;
• whether source visibility persists across Google AI Overviews, Google AI Mode, ChatGPT and other engines; and
• whether company mentions and recommendations move alongside source visibility.

The defensible claim is measured citation visibility, not that an AI platform "trusts" a publisher or that a citation caused a recommendation.

How This Study Relates to Prior Reddit and Health AI Research

Independent research is directionally consistent with a gradual Reddit decline on Google's AI surfaces, but the exact percentages are not directly comparable.

PromptWatch measured Reddit's share of Google AI Overviews citations moving from about 2.37% in early July to 2.10% in mid-August 2026, an 11.3% relative decline with no single break point. Article 52 shows the same gradual direction over a different population and longer window: full-panel Reddit event share moved 1.64% to 1.50% to 1.31%, while the balanced endpoint declined 22.2%. The magnitudes should not be merged because the prompt populations, dates, denominators and collection systems differ.

Ahrefs' September 2026 broad U.S. Google AI Overviews leaderboard ranked Reddit #2 at 18.5% mention share, behind YouTube at 22.9%. That broad all-topic prominence can coexist with Reddit ranking #5 at 5.82% response coverage across this three-month Health and Medical source study and #8 at 5.09% coverage in September. Ahrefs uses a broad U.S. all-topic query universe and a mention-share denominator, while Article 52 uses high-stakes commercial health prompts and reports response citation coverage plus citation-event share.

BrightEdge's August 2026 healthcare analysis found Google AI Overviews moving toward a more platform-heavy source mix than ChatGPT. In its indexed healthcare series, YouTube reached 158 relative to a June baseline of 100 by the week of August 23, while NIH was at 83 and Cleveland Clinic at 108. That is directionally consistent with YouTube ranking #1 in the LLMAI Google AI Overviews Health source study, but BrightEdge's prompt population and indexed metric are different and should not be merged numerically with Article 52.

Conductor's 2026 Health Care benchmark reports that 48.7% of page-one Google queries in its healthcare sample produced an AI Overview and that Healthline led AIO share of voice at 5.76% across its broader industry framework. Conductor's analysis uses a different industry-domain and query methodology, so those percentages are context rather than direct benchmarks for this commercial decision panel.

Taken together, the outside research strengthens the case for measurement discipline, not a universal Reddit or healthcare-source narrative. The defensible comparison is direction, platform specificity, intent, source role and methodology, not decimal-point equivalence across unrelated panels.

How This Study Is Different

This study narrows the broader Reddit health trend research to one platform, one high-stakes commercial family, and one fixed three-month window.

It combines:

1. a 4,160-response Google AI Overviews health and medical source slice;
2. a balanced 13-vertical July-to-September endpoint;
3. a 548-scenario matched prompt-plus-surface test;
4. both citation-event share and response citation coverage;
5. a fresh 14-vertical platform-specific audit, with Medical Alert Systems explicitly identified as missing in July; and
6. a matched Reddit-loss source redistribution audit.

The question is narrow and commercial: how stable was Reddit as a directly cited source in Google AI Overviews for consequential health and medical consumer decisions during this quarter?

Why AI Citation Studies Can Disagree

Two well-executed studies can report different Reddit trends without either one necessarily being wrong.

Query population

Health and medical commercial questions are not representative of the entire web. Reddit's role can differ in software, travel, entertainment, troubleshooting and general informational queries.

Platform surface

Google AI Overviews can behave differently from Google AI Mode, ChatGPT, Gemini, Perplexity or Microsoft Copilot.

Denominator

Citation-event share and response citation coverage measure different things. A source can lose event share while coverage moves less, or vice versa.

Time window

A short product change and a three-month endpoint comparison answer different questions.

Missing versus zero

Medical Alert Systems has no July source dataset. That missing month is not converted into a measured zero. Studies that treat unavailable observations differently can produce different category-level rates.

Prompt weighting

This study does not weight prompts by search volume, patient volume, media spend, treatment value, conversion probability or revenue.

Matching contract

The matched panel requires the same normalized prompt and Google AI Overviews surface in July and September, with unambiguous eligible observations after exact-repeat handling. Aggregate monthly and matched results therefore answer related but different questions.

Domain and infrastructure handling

Domains are consolidated at the registrable-domain level. Obvious navigation or technical infrastructure is excluded from publisher analysis. The published Article 24 frozen rule set removed no infrastructure citations from this specific Google AI Overviews Health and Medical slice.

The useful conclusion is not that one universal Reddit citation percentage exists. Citation visibility is conditional on platform, category, prompt set, time period, denominator and collection method.

Verticals Covered

The Google AI Overviews Health and Medical source study covers 14 vertical labels:

• 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
• Weight Loss and Metabolic Health

Thirteen are present in both July and September. Medical Alert Systems is present later in the quarter but has no July source dataset in the frozen corpus.

Methodology

Source archive

This study uses the frozen July-September 2026 LLM Authority Index archive underlying the Health and Medical citation-source study and the parent Health and Medical Reddit decline study.

Eligibility

A record is eligible when it is:

• in July, August or September 2026;
• assigned to the Google AI Overviews platform family;
• associated with the Health and Medical family; and
• not explicitly marked as an extraction failure.

Exact-repeat anti-double-counting

An observation is treated as an exact analytical repeat when all of the following match:

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

One analytical record is retained while source-dataset memberships are preserved for vertical analysis.

Prompt normalization

Prompt text is normalized with Unicode NFKC normalization, case folding, whitespace collapse and trimming.

Domain normalization

Citation URLs are parsed to hostname, lowercased, stripped of a leading www., and consolidated to registrable domain using Public Suffix List logic.

Reddit identification

Reddit is identified at the registrable-domain level as reddit.com.

Citation-event share

Reddit citation-event share = Reddit citation events / all eligible public citation events

A response can contribute more than one Reddit citation event if multiple eligible Reddit URLs appear.

Response citation coverage

Reddit response citation coverage = eligible responses citing Reddit at least once / all eligible responses

Reddit counts no more than once per response for this metric.

Balanced endpoint

The headline July-to-September endpoint excludes Medical Alert Systems because the frozen archive contains no July dataset for that vertical. The other 13 verticals are present at both endpoints.

Matched prompt-plus-surface test

The matched analysis compares scenarios with the same normalized prompt and Google AI Overviews surface in July and September. The resulting panel contains 548 scenarios, with 24 both, 25 losses, 15 gains, and 484 neither.

Vertical audit

The vertical table is calculated directly from the frozen Google AI Overviews Health and Medical slice. Missing July Medical Alert Systems data is reported as unavailable rather than zero.

Replacement-source audit

For matched scenarios where Reddit appeared in July but not September, the analysis identifies registrable domains present in September but absent from the paired July citation set. Newly appearing domains can co-occur, so the table is not a mutually exclusive attribution model.

Limitations

1. The study covers one frozen three-month research window and should not be treated as a permanent platform rule.
2. Prompt sets are research panels, not search-volume-weighted market-share samples.
3. Visible citation does not prove recommendation causality, hidden retrieval influence or training-data use.
4. The study measures captured public-facing sources and cannot observe every internal retrieval step.
5. Health vertical labels are source dataset labels and are not statistically independent clinical categories.
6. Some small verticals have very low endpoint Reddit counts, so relative percentage changes can be volatile.
7. Medical Alert Systems lacks a July source dataset and is excluded from the balanced endpoint.
8. The matched Google AI Overviews loss-gain imbalance is directionally negative but not statistically significant at p < 0.05.
9. Newly appearing September domains are descriptive co-occurrences, not proven substitutes for Reddit.
10. Platform behavior can change after the research window.

Commercial Disclosure

LLM Authority Index is affiliated with CiteWorks Studio and related AI-search research and services. This research is designed to document observed AI citation behavior. Commercial relationships do not alter the frozen source corpus, eligibility rules, matching logic or published denominators.

No company can purchase a ranking, recommendation, score or position in this study. Citation visibility should not be interpreted as an endorsement by LLM Authority Index or by Google.

References

1. LLM Authority Index. The 2026 AI Citation Authority Study: Which Websites Does AI Cite for High-Stakes Decisions? https://llmauthorityindex.com/resources/research/2026-ai-citation-authority-study-high-stakes-consumer-decisions
2. LLM Authority Index. The Most-Cited Websites in AI for High-Stakes Health and Medical Consumer Decisions. https://llmauthorityindex.com/resources/research/most-cited-websites-ai-health-medical-high-stakes-consumer-decisions
3. LLM Authority Index. Reddit's Decline in AI Citations for High-Stakes Health and Medical Consumer Decisions. https://llmauthorityindex.com/resources/research/reddit-ai-citation-decline-health-medical-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. https://llmauthorityindex.com/resources/research/top-100-google-ai-overviews-citations-health-medical-high-stakes-consumer-decisions
5. LLM Authority Index. The Persistence-Portability Gap: Why AI Citation Authority Persists Over Time but Fragments Across Platforms. https://llmauthorityindex.com/resources/measurement/persistence-portability-gap
6. PromptWatch. Why Did ChatGPT Stop Citing Reddit? Inside the August 2026 Citation Collapse. https://promptwatch.com/blog/chatgpt-stop-citing-reddit
7. Ahrefs. The 50 Most-Cited Websites in Google AI Overviews (September 2026). https://ahrefs.com/blog/most-cited-domains-ai-overviews/
8. BrightEdge. Institution or Platform: What Health and Finance Citations Reveal About ChatGPT and Google AI Overviews. https://www.brightedge.com/resources/weekly-ai-search-insights/ai-overviews-chatgpt-authority-health-finance
9. Conductor. Health Care Industry: 2026 AEO / GEO Benchmarks. https://www.conductor.com/academy/health-care-aeo-geo-benchmarks/

Related LLM Authority Index Research

Corpus foundation and measurement framework

• 2026 AI Citation Authority Study
• Overall Reddit Citation Decline Study
• Cross-Platform Citation Overlap Study
• AI Citation Drift Study
• Overall Google AI Overviews Top 100 Study
• Persistence-Portability Gap Framework

Health and Medical source-market branch

• All-Platform Health and Medical Citation Authority Study
• Google AI Overviews Health and Medical Citation Sources
• Google AI Mode Health and Medical Citation Sources
• ChatGPT Health and Medical Citation Sources
• Perplexity Health and Medical Citation Sources
• Gemini Health and Medical Citation Sources
• Microsoft Copilot Health and Medical Citation Sources

Health and Medical Reddit-trend branch

• Health and Medical Reddit Decline 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