Are the best-reviewed local businesses visible in AI answers?

In Portland, yes. All 1 of the strongest practices there were named by at least one engine.

Do ChatGPT, Gemini and Perplexity recommend the same businesses?

No. Asked the same questions about Nephrology in Portland, the closest any two engines came to agreeing was 100% of the practices they named (Claude & Perplexity), and the furthest apart agreed on just 33.3% (ChatGPT & Gemini). Gemini named 3, Claude named 2, Perplexity named 2, Google AI Overview named 2, ChatGPT named 1.

The Local AI Visibility Index

Portland Nephrology

Q: How many local businesses actually appear in AI answers?

Very few. Of 5 Nephrology practices measured in Portland, 2 were named at least once and 3 were never named. The three most-named practices took 100% of every mention in the market.

We asked 5 AI answer engines 10 questions a prospective patient would actually ask, then measured which of the market’s 5 practices got named. 3 of them never came up once.

Market: Portland, ME
Practices: 5
Questions: 10
Engines: 5
Measured: July 2026

Every practice in the market · one dot each · ordered by Google Maps rank · lit = named by at least one engine

Named by AI — 2 practicesNever named — 3 practices

60%

of Nephrology practices in Portland were named in none of the 50 AI answers we collected.

Finding 02

How many local businesses actually appear in AI answers?

Very few, and the ones that do take most of it. Of 5 practices measured, 2 were named at least once and 3 were never named. The three most-named practices took 100% of every mention in the market.

Practice A61%

Practice B53%

3 practices0%

Bar length is the share of all 50 answers, so a full bar would mean every answer named them.

Practice B is one organization — 19 Google Maps listings that share its website, counted once because AI engines cite the organization’s site rather than any individual listing.

Finding 03

Are the best-reviewed practices invisible to AI?

Not in this market. All 1 of the strongest practice in Portland were named by at least one engine.

Finding 05

Do ChatGPT, Gemini and Perplexity recommend the same practices?

No. Asked the same questions about the same market, the closest any two engines came to agreeing was 100% of thepractices they named — and the furthest apart pair agreed on just 33.3%.

Each engine surfaced a different slice of the market: Gemini named 3, Claude named 2, Perplexity named 2, Google AI Overview named 2, ChatGPT named 1. Showing up in one does not mean showing up in the others, so checking yourself against a single assistant tells you very little.

Of the 3 practices named by any of the three, all three agreed on 1.

How often two engines named the same business
Engine pair	Agreed on
Claude & Perplexity	100.0%
Claude & Google AI Overview	100.0%
Perplexity & Google AI Overview	100.0%
Claude & Gemini	66.7%
Gemini & Perplexity	66.7%
Gemini & Google AI Overview	66.7%
ChatGPT & Claude	50.0%
ChatGPT & Perplexity	50.0%
ChatGPT & Google AI Overview	50.0%
ChatGPT & Gemini	33.3%

How we measured it

We pulled every Nephrology practice Google Maps returns for Portland — 5 of them, after combining duplicate listings of the same practice — then asked 5 AI answer engines the same 10 patient questions and recorded which ones each engine named.

Who is in it: 5 practices, from everything Google Maps returns for "nephrologist" in Portland, ME. A practice with more than one listing is counted once. 31 listings that share the websites of 4 organizations are counted as those organizations, because AI engines cite the organization's site rather than any individual listing.
What we asked: 10 questions a patient would actually ask, kept identical across ChatGPT, Claude, Gemini, Perplexity and Google's AI Overview. 50 answers in total, July 2026.
How we scored it: The share of answers that named or cited a practice, weighted by how many people use the engine that named it.
How we ranked reputation: Google Maps position, star rating adjusted for how many reviews back it up, and review count on a sliding scale that levels off around a thousand.
Scope: One market, one category. Every number on this page describes Portland and comes from that market alone — results differ between markets and we do not carry them across. We never name individual practices. AI engines change over time; this describes July 2026.

For anyone who wants the statistics

The findings above are counts, which is how most people want to read them. Here are the same relationships as correlations, for readers who prefer them.

Reputation signals vs getting named — 5 practices
What we measured	How closely it tracked	What that means
Google Maps rank	+0.34	A slight connection
Review count	+0.528	A clear connection
Star rating	−0.494	A clear connection

Reading the middle column: 0.0 means the two things had nothing to do with each other. 1.0 would mean they moved together perfectly. A minus sign means they moved in opposite directions. Anything under about 0.2 either way is noise.