The 100 Most-Cited Websites in Microsoft Copilot for High-Stakes Health and Medical Consumer Decisions

LLM Authority Index Research | Microsoft Copilot | Health and Medical | July-September 2026

Microsoft Copilot uses a distinct source market when consumers ask high-stakes questions about treatment centers, fertility care, hearing aids, home health, medical alert systems, telehealth, online pharmacies, therapy, STD testing and metabolic-health services.

Across 1,511 deduplicated Microsoft Copilot responses covering 14 health and medical decision verticals, Forbes ranked #1, appearing as a cited domain in 10.32% of eligible responses. Healthline ranked #2 at 8.80%, NCOA.org #3 at 7.54%, and GoodRx #4 at 5.69%. Google.com and Amazon each appeared in 5.16% of responses; Google.com ranks #5 under the response-count, citation-event, domain-name tie-break used for the table.

The public publisher ranking requires a Copilot-specific source audit. The deduplicated health slice contained 7,414 captured citation entries before infrastructure filtering. The final ranking removes 1,300 Bing/OpenStreetMap technical and navigational entries, leaving 6,114 substantive citation events across 1,335 cited registrable domains.

The category source map is also much more specialized than the Copilot-wide leaderboard. Only 35 of the health and medical Top 100 domains also appear in Copilot's overall Top 100, a 21.2% Jaccard similarity.

Answer Capsule

Forbes was the most frequently cited website in Microsoft Copilot for high-stakes health and medical consumer decisions in the July-September 2026 LLMAI panel. It appeared in 156 of 1,511 eligible responses, or 10.32%. Healthline followed at 8.80%, NCOA.org at 7.54%, and GoodRx at 5.69%. Google.com and Amazon each appeared in 5.16% of responses. After removing 1,300 Bing/OpenStreetMap technical and navigational entries, the study counted 6,114 substantive citation events, 4,851 domain-response appearances, and 1,335 distinct cited domains.

Key Findings

• Forbes ranked #1 overall at 10.32% response citation coverage.
• Healthline ranked #2 at 8.80%, NCOA.org #3 at 7.54%, and GoodRx #4 at 5.69%.
• Google.com and Amazon each appeared in 5.16% of eligible responses. Google.com ranks #5 because it had more citation events under the table's tie-break.
• The 1,511-response denominator matches the Copilot slice reported in the parent Health and Medical category study.
• The public ranking contains 1,335 cited domains, 4,851 domain-response appearances, and 6,114 substantive citation events.
• The Top 10 domains account for 18.5% of domain-response appearances, while the Top 100 account for 53.7%. This is less concentrated than Copilot overall at the same ranking depths.
• Only 35 domains overlap between the health Top 100 and Copilot's overall Top 100.
• Healthline, NCOA.org, GoodRx, HelpGuide.org, HearingTracker and Audiologists.org all have roughly 4.6x to 4.8x their Copilot-wide response coverage inside this category.
• Forbes ranked #1 in July and August. Google.com moved to #1 in September.
• Only 40 domains remained in the health Top 100 in all three months, with a 38.9% median monthly Top 100 Jaccard similarity.
• The public table excludes 1,105 bing.com, 181 bing.net, 12 bingapis.com, and 2 openstreetmap.org technical/navigation entries.

Questions This Study Answers

• Which websites dominate Microsoft Copilot citations for high-stakes Health and Medical decisions, and how does that source hierarchy change by vertical?
• How persistent is Copilot's Health and Medical source market over time, and how portable is that visibility to other AI platforms?
• What should health publishers, provider brands, healthcare marketers and CMOs measure before allocating resources to Copilot-focused content, PR, partnerships or earned media?

Why This Research Belongs in Daily AI Search Marketing Decisions

Article 42 sits at the intersection of two commercially useful views of the same source market:

• the Microsoft Copilot platform view, which asks which sources recur across high-stakes consumer decisions on Copilot; and
• the Health and Medical decision-family view, which asks which sources recur across six AI platform families for one high-stakes category.

For publishers and specialist health sites, that intersection supports a more precise claim than saying a domain is simply "visible in Copilot." A source can document whether it is cited specifically for health and medical consumer decisions, whether that visibility persists over time, and whether its source presence is broad across multiple health verticals or concentrated in one specialist decision journey.

For healthcare brands, providers, medical-device companies, senior-care businesses, CMOs, PR teams and agencies, the operating question is:

Which sources are already present around the exact health decisions our customers ask Microsoft Copilot to help them make?

Six findings matter for daily planning:

• the Top 100 account for 53.7% of domain-response appearances in this Copilot Health and Medical slice;
• the Top 10 account for only 18.5%, making this source market notably diffuse at the head;
• only 35 domains overlap between this Health and Medical Top 100 and Copilot's broader High-Stakes Top 100, a 21.2% Jaccard similarity;
• 40 domains remained in the monthly Health and Medical Top 100 in July, August and September, and the median of the three monthly Top 100 Jaccard comparisons was 38.9%;
• the final child-study Top 100 lists show Copilot sharing 41 domains with Google AI Overviews, 38 with Google AI Mode, 38 with Perplexity, 33 with Gemini and 32 with ChatGPT; and
• 1,300 Bing, Bing API, Bing network and OpenStreetMap technical or navigation entries were excluded before constructing the public source leaderboard.

The last point is especially important for Copilot. Microsoft's current documentation says Copilot can generate web-search queries and send them to the Bing search service to ground responses in web data. Raw citation captures can therefore contain search, map, image, favicon, API and navigation infrastructure that should not be interpreted as editorial publisher authority. Microsoft Learn: web search in Microsoft Copilot

The parent Health and Medical Citation Authority Study provides the category-level Persistence-Portability Gap interpretation. It 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.

Article 42 answers a narrower Copilot-specific question. Its 38.9% median monthly Top 100 persistence should not be subtracted from one pairwise cross-platform overlap to create a Copilot-specific gap. The parent PPG uses category-level summary statistics across the broader family.

The parent family is also highly fragmented across engines. The final six Health and Medical platform studies contain 290 distinct Top 100 domains in their combined union. Only 20 domains appear in all six platform Top 100 lists, while 161 appear in only one.

There is also a Copilot-specific filtering caveat. The parent Health summary displayed bing.com among Copilot's leading sources. Article 42 keeps the same 1,511-response denominator but applies the publication plan's infrastructure audit before ranking public sources, excluding Bing and OpenStreetMap technical or navigational surfaces. This is a source-classification refinement, not a denominator change.

Citation visibility should remain separate from brand mentions, recommendation rate, ranking, sentiment, citation-recommendation coupling, clinical quality, treatment safety and downstream business outcomes. A source can be frequently cited without causing Copilot to recommend a specific provider, product, clinic or treatment, and citation frequency does not validate medical advice.

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

The daily operating model is therefore four-layered:

1. Current Copilot Health core: maintain the sources that matter now, with the collection date attached.
2. Vertical and prompt-cluster layer: identify which sources dominate the exact hearing-aid, medical-alert, pharmacy, online-doctor, fertility, addiction-treatment, dental, therapy or other health 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, Google AI Mode, ChatGPT, Perplexity and Gemini.

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

Article 42 is the intersection of two parent studies:

• The Microsoft Copilot 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 Microsoft Copilot for Health and Medical Decisions.

Articles 24, 25, 26, 40 and 41 provide the same Health and Medical decision-family cut for Google AI Overviews, Google AI Mode, ChatGPT, Perplexity and Gemini.

What We Studied

This study isolates Microsoft Copilot responses associated with the Health and Medical family of the frozen LLM Authority Index High-Stakes Consumer Decisions corpus.

The family contains 14 source vertical labels:

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

Study size

Responses by month

The primary ranking metric is Response Citation Coverage: the percentage of eligible Copilot health responses that cited a domain at least once. A domain counts no more than once within a response for the primary metric even when Copilot surfaces multiple pages from the same site.

Medical Alert Systems has no July source file in the frozen archive. Missing source-months are treated as unavailable rather than as zero-citation observations.

The Top 25 Microsoft Copilot Health and Medical Citation Sources

This is a source-visibility ranking, not a medical-quality score, clinical-authority score, recommendation score, safety assessment or endorsement. A domain's position indicates how often it appeared as a visible cited source within this measured Copilot health and medical panel.

The Full Top 100 Microsoft Copilot Health and Medical Citation Sources

Citation Concentration

Copilot's health and medical source market has a relatively long tail compared with Copilot's overall high-stakes source distribution.

The health Top 100 account for 53.7% of response-level domain appearances, compared with 56.7% for Copilot overall. At the Top 10 level, health is substantially less concentrated: 18.5% versus 30.0% overall. That makes specialist discovery especially important in this category.

Health and Medical Specialization vs. Microsoft Copilot Overall

Only 35 of the health and medical Top 100 domains also appear in Copilot's overall Top 100. That is a 21.2% Jaccard similarity between the two sets.

The category-lift table shows why a platform-wide source list is incomplete for health and medical research.

Forbes behaves differently from the specialist health leaders: it is #1 in the category, but its health coverage is about half its Copilot-wide coverage because Forbes is already the dominant source across the broader high-stakes Copilot panel. Healthline, NCOA.org, GoodRx, HelpGuide.org, HearingTracker, MedSwitcher and Audiologists.org all become several times more prominent once the analysis is restricted to health decisions.

The Most-Cited Sources by Individual Health and Medical Vertical

The vertical cuts show that the category-wide leaders do not dominate every health decision. Hearing-aid research is led by NCOA.org and HearingTracker. Dental implants elevate AffordableDentures and Aspen Dental. Online therapy elevates HelpGuide, Forbes and ChoosingTherapy. Addiction Treatment Centers elevate Hazelden Betty Ford, Statista and American Addiction Centers. Fertility and IVF queries elevate Google.com and clinic-specific sources.

Breadth vs. Specialization

Copilot's health source market contains several different kinds of authority.

Broad category sources

Forbes appears across 10 of the 14 health source verticals. Google.com appears across 13, while Amazon appears across 7. These domains can surface across multiple buyer journeys, although their roles differ materially by query.

Specialist health sources

HearingTracker and Audiologists.org are concentrated in hearing-aid prompts. AffordableDentures and Aspen Dental over-index in dental implants. HelpGuide and ChoosingTherapy are particularly strong in online therapy. These sources may matter more for a narrow campaign than their overall platform rank suggests.

Provider and first-party sources

The vertical tables also include provider-owned domains such as Hazelden Betty Ford, Home Instead, CCRM IVF, ClearChoice and others. Citation visibility in this study describes observed source presence, not an independent quality assessment of those providers.

Monthly Persistence and Citation Drift

The Copilot health source market changed materially across July, August and September.

Only 40 domains appeared in the monthly health Top 100 in all three months. The median of the three monthly Top 100 Jaccard comparisons was 38.9%.

Forbes ranked #1 in July and August, then moved to #7 in September. Google.com, which ranked #9 in July and #17 in August, moved to #1 in September. Healthline stayed near the top at #2, #3 and #4. NCOA.org moved from #5 to #2 to #3.

Monthly movement should be interpreted as source-market drift inside this fixed panel. It can reflect retrieval changes, indexing, source availability, prompt mix within a month, ranking behavior and other factors. It does not by itself establish why a domain moved.

Platform Differences: Microsoft Copilot's Health and Medical Source Market Is Not Interchangeable With Other AI Engines

The final Health and Medical child-study Top 100 lists show meaningful cross-platform overlap, but no other measured engine uses the same source portfolio.

Copilot is closest to Google AI Overviews in this decision family, but even that pair shares only 41 of its Top 100 domains. Google AI Mode and Perplexity are somewhat farther away, while Gemini and ChatGPT diverge further.

The ranking order also differs materially. The audited Copilot public-source ranking begins with Forbes, Healthline, NCOA, GoodRx and Google.com. Perplexity begins with Healthline. Gemini begins with GoodRx. ChatGPT gives Healthline, Forbes and Reddit much greater coverage. The two Google AI search surfaces also use different source hierarchies.

The parent Health study reports only 20 domains present in all six platform Top 100s, while 161 domains appear in only one platform's Top 100. That is a strong signal that healthcare source planning should preserve both a cross-platform core and engine-specific specialist layers.

The older parent category summary displayed bing.com among Copilot's leading domains. Article 42 removes Bing search, maps, image, thumbnail, favicon/API and related technical surfaces before the public publisher ranking, while preserving the same 1,511-response denominator.

The operating implication is to maintain three layers: a cross-platform Health and Medical core, a Copilot-specific source layer, and a vertical-specific specialist layer.

This section answers

• Do the same publishers and health sources lead every AI platform?
• Which engines share the most Copilot Health and Medical sources?
• Should a healthcare brand use one universal outreach list for all AI platforms?

Prior Research and Why the Rankings Can Look Different

Ahrefs: broad U.S. all-topic Copilot queries

Ahrefs' September 2026 Copilot study tracks more than 3 million U.S. queries across all topics. Amazon ranks #1 at 16.8% mention share, Walmart #2 at 12.6%, Wikipedia #3 at 7.6%, ScienceInsights #4 at 3.5%, and EngineerFix #5 at 3.3%. Ahrefs: The 50 Most-Cited Websites in Copilot

That is very different from Article 42, where the audited health ranking begins with Forbes at 10.32% response citation coverage, Healthline at 8.80%, NCOA at 7.54% and GoodRx at 5.69%.

The difference is not a contradiction. Ahrefs measures broad all-topic mention share among its top sources, while Article 42 measures response-level domain presence inside a fixed high-stakes Health and Medical decision panel.

Microsoft: Copilot web grounding can use Bing search

Microsoft's current documentation says Microsoft Copilot and Copilot Chat can generate search queries from a user's prompt and send them to the Bing search service to ground responses in web data. Microsoft Learn: web search in Microsoft Copilot

That architecture makes technical-source auditing especially important. Article 42 excludes 1,105 bing.com entries, 181 bing.net, 12 bingapis.com, and 2 openstreetmap.org entries before ranking public-facing sources.

Machine Relations: health source leaders change with question shape

Machine Relations' September 23, 2026 Index release covers 23,280 cited domains, 129,264 citation events and 16,475 observed answer runs across its six-engine system. In Consumer Health, Healthline leads the best-tools question shape at 43.2%, while UCLA Health leads the is-it-worth-it shape at 37.7%. In Healthcare Services, OmniMD leads best-tools at 32.7%, while NIH leads is-it-worth-it at 26.2%. Machine Relations Index Report, September 23, 2026

Machine Relations does not include Microsoft Copilot in that engine set, so those figures are not Copilot evidence and should not be merged with Article 42. The useful agreement is methodological: health source leadership changes with the question shape, engine set and measurement contract.

Tinuiti: OTC health is tracked separately across Copilot and other engines

Tinuiti's Q3 2026 AI Citation Trends Report tracks ChatGPT, Perplexity, Google AI Mode, Google AI Overviews, Google Gemini and Microsoft Copilot across commercial categories including OTC health. Tinuiti Q3 2026 AI Citation Trends Report

Tinuiti's OTC health prompt set is not the same as Article 42's Health and Medical family, so its percentages should not be imported into this ranking. The useful agreement is methodological: Copilot source behavior should be validated against the exact health category and prompt population being measured.

Studies can disagree because of:

• query selection
• health vertical mix
• commercial intent
• geography
• time window
• ranking metric
• citation-event versus response-level counting
• source-type classification
• technical-asset exclusions
• domain normalization
• platform mode and retrieval behavior

The relevant question is not which ranking is universally correct. It is which ranking matches the health decision environment and measurement contract a publisher, provider or brand actually cares about.

Why This Study Is Different

This article is not merely a list of Copilot citations. It combines:

• a high-stakes consumer health decision focus;
• 14 source vertical labels covering treatment, hearing, senior care, telehealth, pharmacy, therapy, testing and metabolic-health decisions;
• a three-month July-September 2026 observation window;
• 1,511 deduplicated eligible Copilot responses;
• primary response-level domain coverage rather than raw URL frequency alone;
• a category-specific Copilot capture audit removing 1,300 Bing/OpenStreetMap technical entries;
• monthly Top 100 persistence measurements;
• vertical-level leaders;
• category lift versus Copilot overall; and
• direct Top 100 overlap against the five other published AI platform source maps.

Why AI Citation Studies Can Disagree

Two Copilot citation studies can both be methodologically sound and still produce different rankings.

Important reasons include:

• broad informational prompts versus commercial buyer-intent prompts;
• all topics versus health and medical decisions;
• exact product surface or account context;
• geography and language;
• whether web grounding is enabled or available;
• Bing retrieval and presentation changes;
• whether Bing search, maps, images, thumbnails and favicon/API infrastructure are filtered;
• URL-level counting versus registrable-domain counting;
• raw citation-event counts versus one-domain-per-response coverage;
• treatment of platform-owned sources;
• collection dates; and
• the exact prompt population.

That is why this article publishes its denominator, technical exclusions, verticals and primary metric rather than presenting the Top 100 as a universal Copilot ranking.

What This Means for Health and Medical Publishers

Publishers can use the study to document measured AI source visibility, but the language should stay observational.

A publisher can responsibly describe:

• response-level citation coverage;
• category rank;
• vertical breadth;
• monthly persistence;
• category lift versus Copilot overall; and
• whether its visibility is broad or specialist.

A publisher should not claim that frequent citation proves medical accuracy, clinical authority or that buying advertising or sponsored content will cause Copilot to recommend an advertiser.

Questions publishers can answer with this study

• Does our site have broad Copilot visibility across health decisions or specialist depth in one vertical?
• Is our source visibility persistent across months or concentrated in one period?
• Do we materially over-index inside health compared with Copilot overall?

What This Means for Brands and CMOs

For healthcare brands, agencies and digital PR teams, the source map can help prioritize earned-media research.

1. Start with the exact buyer journey

A hearing-aid brand should not use the same source list as an online pharmacy, fertility clinic or therapy platform merely because all sit inside a broad health family.

2. Separate broad publishers from specialists

Forbes and Healthline offer broad category visibility. HearingTracker, Audiologists.org, ChoosingTherapy, AffordableDentures and other specialists can be more relevant in a narrow prompt cluster.

3. Treat platform differences as material

Copilot's health Top 100 shares only 32 domains with ChatGPT's health Top 100 and 33 with Gemini's. A universal AI outreach list will miss platform-specific sources.

4. Audit Copilot capture before making decisions

Raw Copilot exports can contain substantial Bing/OpenStreetMap infrastructure. Publisher prioritization should be based on the audited public-source layer, not unfiltered capture counts.

5. Track citation presence separately from recommendations

Citation visibility establishes a source relationship, not that a source caused a company recommendation. Brands should measure source citations, company mentions, recommendations, sentiment and conversion-oriented prompt outcomes separately.

Methodology

Research source

This study uses the frozen July-September 2026 LLM Authority Index High-Stakes Consumer Decisions archive used by the broader 2026 AI Citation Authority Study.

Platform filter

Only observations assigned to the Microsoft Copilot platform family are included. Copilot remains separate from ChatGPT, Gemini, Perplexity, Google AI Overviews and Google AI Mode.

Category assignment

Observations are included when their preserved source memberships belong to the Health and Medical family. The 14 source labels are listed in the What We Studied section.

Exact file deduplication

Byte-identical source files were deduplicated by SHA-256 before observation processing.

Analytical anti-double-counting

Within the category-platform slice, observations were treated as exact analytical repeats when they shared the same report month, exact raw platform/source surface, normalized prompt text and exact set of original citation URLs. One analytical record was retained while preserving originating vertical memberships.

Prompt normalization

Prompt matching uses Unicode NFKC normalization, case folding, whitespace collapse and trimming. Prompt wording is otherwise preserved.

Explicit extraction failures

No Copilot health observation in this slice was explicitly marked as an extraction failure.

Domain normalization

Citation URLs were parsed to hostnames, normalized to lowercase, stripped of leading www., and consolidated to registrable domains using Public Suffix List logic.

Copilot capture audit and technical exclusions

The deduplicated health response set contained 7,414 captured citation entries before public infrastructure filtering. The public ranking excludes 1,300 obvious technical or navigational entries, consisting of 1,105 bing.com, 181 bing.net, 12 bingapis.com, and 2 openstreetmap.org entries.

These entries include Bing search/map wrappers, image and thumbnail infrastructure, favicon/API assets and OpenStreetMap navigation utilities. The exclusion is based on the role of the surfaced URL, not simply on Microsoft ownership. Substantive publisher pages remain eligible.

Primary metric

Response Citation Coverage = eligible Copilot health responses citing domain d at least once / all eligible Copilot health responses.

The denominator for this article is 1,511 responses. A domain counts no more than once per response for this metric.

Secondary metric

Citation events are retained as a secondary metric. A response can contain multiple citation events from the same domain even though the domain counts once for response coverage.

Monthly ranks

July, August and September Top 100 lists are calculated independently from eligible responses in each month using the same public-source rules.

Vertical views

A deduplicated response can retain more than one originating source membership when overlapping exports contain the same exact observation. Vertical tables are therefore descriptive source views and are not assumed to be statistically independent.

Missing July data

Medical Alert Systems has no July source file because that dataset was not produced in July. Missing source-months are treated as unavailable rather than as zero-citation observations.

Reconciliation with the parent Health and Medical article

The parent cross-platform Health and Medical article reports 1,511 Microsoft Copilot responses for this family, matching this child study's reconstructed denominator.

The parent summary also displayed bing.com among the leading Copilot sources. Article 42 applies the required Copilot capture audit and removes Bing/OpenStreetMap technical and navigational surfaces before constructing the public publisher ranking. This is a filtering refinement, not a change to the eligible-response denominator.

Jaccard overlap

Top 100 Jaccard similarity is calculated as shared Top 100 domains / unique domains across the two Top 100 lists.

No causal interpretation

A visible citation establishes an observed source relationship. It does not prove that the citation caused Copilot to mention, rank, recommend or convert a consumer for any company, provider, treatment or service.

Limitations

1. This is a fixed commercial prompt panel, not all medical information seeking or all Copilot usage.
2. Health and medical source labels are commercial decision groupings, not a representative clinical sample.
3. Medical Alert Systems has no July source file. Missing source-months are not imputed.
4. Copilot capture contains substantial technical Bing infrastructure. The public audit removes the known Bing/OpenStreetMap artifact classes documented above, but future product-surface changes could introduce new types.
5. Citation presence is not medical validation. Frequency in this panel does not establish clinical accuracy, safety, quality or endorsement.
6. Citation presence is not recommendation causality. A source can support background information or one factual statement without causing a company recommendation.
7. Vertical memberships can overlap because exact repeated observations are retained once for aggregate analysis while preserving their originating source labels.
8. Platform behavior changes. Copilot retrieval, ranking and presentation can shift after the July-September 2026 window.
9. Monthly Top 100 persistence is not prompt-level persistence. A domain can stay in the Top 100 while appearing on different prompts or URLs.

Commercial Disclosure

LLM Authority Index publishes independent citation measurement and related AI-search research. Rankings in this study are based on the frozen source corpus and stated methodology. No company can purchase a ranking, recommendation, score or position in this research table. Commercial relationships, advertising or related services do not change the ranking calculation.

References

1. LLM Authority Index: 2026 AI Citation Authority Study
2. LLM Authority Index: Most-Cited Websites in AI for Health and Medical Decisions
3. LLM Authority Index: Microsoft Copilot Platform Top 100
4. LLM Authority Index: Persistence-Portability Gap
5. Ahrefs: The 50 Most-Cited Websites in Copilot, September 2026
6. Microsoft Learn: Data, privacy, and security for web search in Microsoft Copilot
7. Machine Relations: Index Report, September 23, 2026
8. Tinuiti: Q3 2026 AI Citation Trends Report

Related LLM Authority Index Research

Parent studies and measurement framework

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

Sibling Health and Medical platform studies

• Google AI Overviews
• Google AI Mode
• ChatGPT
• Perplexity
• Gemini

Reddit trend studies for this category

• 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

Article 42 is the Microsoft Copilot x Health and Medical intersection study. The parent articles explain the broader platform and decision-family markets. The sibling platform studies show portability across engines. The Reddit studies provide one longitudinal source example inside the same Health and Medical decision family.