Does AI recommend the same dental clinics in English and Spanish?
“Which dental clinics in Mexico offer a warranty on implants and crowns?” We asked Claude three times in English. Each time it named the same four clinics. In three Spanish answers to the equivalent question, only one of those four names carried over. It appeared all three times.
Would the names have changed if we had simply asked again? We tested four patient questions on ChatGPT, Claude, Gemini and Perplexity, three times per language. That gave us 96 answers.
How much did the clinic shortlists overlap?
- Repeat the question in the same language
- 39.4%
- Compare English with Spanish
- 22.9%
Average share of distinct clinic names that appeared in both answers being compared.
The warranty question showed the biggest difference
Across all four assistants, the warranty shortlists overlapped by 60.5% within one language and 20.8% across languages. The broadest question went the other way. When we asked which clinic an assistant would recommend to an American patient, overlap was 27.2% within a language and 31.0% across languages.
Read chart values by question
| Question | Same language | English vs Spanish |
|---|---|---|
| General recommendation | 27.2% | 31.0% |
| US patient reviews | 38.2% | 22.6% |
| Warranty terms | 60.5% | 20.8% |
| Implants in Tijuana | 31.7% | 17.1% |
Compare the four AI assistants
Averaged across the four questions, all four assistants showed less overlap across languages. Claude had the largest gap (59.6% to 21.1%) and Gemini the smallest (31.1% to 24.8%). Gemini’s lists also varied when we repeated a question in the same language.
Read chart values by assistant
| Assistant | Same language | English vs Spanish |
|---|---|---|
| ChatGPT | 29.4% | 21.6% |
| Gemini | 31.1% | 24.8% |
| Perplexity | 37.5% | 23.9% |
| Claude | 59.6% | 21.1% |
What a clinic can check this week
Take one question your patient coordinator hears before booking. Ask it in both languages and open the pages the assistant cites. For a warranty, can a patient find what is covered, for how long, and whom to contact back home?
This one-day study measured which clinics appeared. It did not assess clinical quality or verify warranty claims.
How we measured overlap and set the search location
We counted each clinic brand once per answer. For each pair of answers, we divided the number of names they shared by the total number of distinct names in the pair. If two answers named three clinics each and shared one, the overlap was one out of five, or 20%.
We tested four questions on one day through the providers’ APIs with web search enabled, targeting buyers in the US. Our integration sent a US search-location hint to ChatGPT, Claude and Perplexity. Gemini received no location hint. Looking only at the three assistants that received the hint, overlap averaged 42.2% within a language and 22.2% across languages.
Counting rules and sample size
We grouped spelling variants and identifiable branches of a brand. We excluded names appearing only in citations or as negative examples. Three of the 24 general recommendation answers named no clinic. We compared 95 usable pairs within languages and 144 across languages. One English pair contained two empty lists, so its overlap was undefined. Each answer contributed to several pairs.
For each question and assistant, we averaged the English repeat pairs and the Spanish repeat pairs separately, then gave the two languages equal weight. For the cross-language result, we compared each of the three English answers with each of the three Spanish answers. Each question and each assistant had equal weight in the overall result.
The four questions, as asked
- Which dental clinic in Mexico would you recommend for an American patient?¿Qué clínica dental de México recomendarías a un paciente estadounidense?
- Which dental clinics in Mexico have the best reviews from US patients?¿Qué clínicas dentales de México tienen las mejores reseñas de pacientes de Estados Unidos?
- Which dental clinics in Mexico offer a warranty on implants and crowns?¿Qué clínicas dentales de México ofrecen garantía en implantes y coronas?
- Which dental clinic in Tijuana would you recommend for implants?¿Qué clínica dental de Tijuana recomendarías para ponerse implantes?
Which models we used
ChatGPT (gpt-6-luna), Claude (claude-sonnet-5-5), Gemini (gemini-3.6-flash) and Perplexity (perplexity/sonar). The reported model matched the requested model in all 96 answers.
Curious about the 96 answers? Email me for the anonymised data.