Sources

Where Google AI Overviews, Google AI Mode and ChatGPT got their answers in November 2026. ChatGPT showed no sources for 461 of its 1,074 answers.

The best source each answer cited

Answers that showed sources

AI Overviews 56%14%24% 1,005

AI Mode 75%7%9%9% 1,042

ChatGPT 83%9%7% 613

The NHSAccredited UK source, not the NHSOther UK sources onlyNothing from the UKUnconfirmed

By tool

AI OverviewsAI ModeChatGPT

Listed the NHS or an accredited source first“prioritise … verified NHS and UK-based accredited health information sources” 41%of 1,00576%of 1,04275%of 613

Cited NHS or accredited sources“reference verified NHS and UK-based accredited health information sources” 61%of 1,00582%of 1,04292%of 613

Cited a website from the USA hospital, government site or health publisher based in the US. 69%of 1,00526%of 1,04211%of 613

Cited social media, video or a forumYouTube, Facebook, Reddit, TikTok, Instagram and similar. 42%of 1,0057%of 1,0421%of 613

Most cited, besides the NHS

Answers

The NHS was cited in 1,848 of these 2,660 answers. These are the organisations cited most often after it.

YouTubeVideo317 Mayo ClinicUS hospital223 FacebookForum or social media202 JAMA NetworkUS health website199 GOV.UKUK government195 Cleveland ClinicUS hospital172 National Institute for Health and Care Excellence (NICE)UK government139 PubMed CentralUS government123 Cancer Research UKUK charity on the PIF TICK list122 Centers for Disease Control and PreventionUS government90 NCBI Bookshelf (US National Library of Medicine)US government64 Macmillan Cancer SupportUK charity on the PIF TICK list63 American Academy of Family PhysiciansUS website52 MMedical News TodayUS health website49 HealthlineUS health website46 British Heart FoundationUK charity on the PIF TICK list41