MMI practice · Guide

How to practice for the MMI interview with ChatGPT: three prompts we tested, and where it breaks

Published 22 October 2026 · Tested 22 October 2026

You can use ChatGPT to practice medical school multiple mini interview (MMI) stations for free, including when you have no partner to practice with. It asks good follow-up questions. Two things go wrong without instructions: as an angry patient it turns polite and talks too much, and as a grader it writes your answers for you. Below are three prompts that fixed this in our tests, and the parts they did not fix.

Can you practice the MMI with ChatGPT?

Yes, for part of it. ChatGPT can run an MMI station out loud, ask follow-up questions and grade a transcript, and the free plan covers all three, with a daily limit on voice. What it does not do on its own is keep the clock, play a difficult person without softening, or give you the same advice twice.

Applicants have practiced this way since early 2023. In the r/premed thread “Using ChatGPT to practice for an MMI interview”, a popular tip was about its manners:

“it is designed to be nice so ask it to be ‘a highly critical medical school advisor (or whatever) that is devoted to finding any flaws in a prospective student’”

By 2026 applicants had gone further. They paste a published interviewer guide into the chat and ask ChatGPT to grade against it. A reply on r/premedcanada in May 2026:

“ChatGPT inputted with the mac med MMI grader pamphlet (publicly available) provided me far better feedback than any prep with other applicants/med students did.”

Kyra Yuan Li of Western University and three co-authors described practicing with ChatGPT’s voice in the Canadian Medical Education Journal in 2025, and noted its tone: “The AI provided feedback in a respectful, unbiased, and encouraging tone.” Encouraging helps when you are drafting an answer. In a role-play station it works against you, because the person across from you is meant to be hard to talk to.

Research separates coaching from practice. In a study of 287 applicants to an Australian medical school, Griffin and colleagues found that coaching “does not assist and may even hinder their performance on an MMI”, while repeat candidates improved slightly on stations that were the same as or similar to ones they had seen before. The first MMI study at McMaster, with 117 applicants and 10 stations, found that how well a candidate did varied more from one station to the next than it varied between candidates. So practice on many different stations.

We could not find a peer-reviewed study that measures whether practicing with ChatGPT changes MMI scores. The nearest evidence comes from medical students: in a 2024 Japanese trial, 35 fourth-year students who practiced with AI-simulated patients scored 28.1 out of 31 on the medical interview checklist of a national pre-clinical OSCE, against 27.1 for 110 students from the year before. The trial was not randomized, and it measured clinical interviewing, not admissions.

How do you set up ChatGPT voice mode for a timed MMI station?

Use a new ChatGPT chat for every station. Paste the prompt as a typed message, wait for “Ready.”, then switch to voice and say “start”. Keep time on your phone: two minutes to read the card, eight minutes in the room. In a real MMI nobody waits for you to finish, so stop when the timer does.

1. Timer. Set 2:00 to read the door card, then 8:00 for the station. The prompts below do not ask ChatGPT to watch the clock: a timer on your phone is more reliable.
2. Voice mode. As of 22 October 2026, ChatGPT’s default voice mode is called Live. It listens and speaks at the same time, so it can cut in while you are still thinking. OpenAI’s own help page suggests a fix: “At the start of the conversation, you can ask Live to wait until you are ready for a response.” Prompt 1 builds this in: it waits for “done”, and if you pause before that, it says only “Take your time.”
3. Limits. Free accounts get limited Live time, and OpenAI does not publish the number. Go and Plus get 3 hours in any 24. Live does not use your camera; video exists only in the older Advanced mode on phones, for eligible subscribers.
4. Privacy. For grading, which is typed, open a temporary chat and choose Unpersonalized. It stays out of your history and is not used to train models while it stays temporary. Voice audio is kept with the transcript for 30 days. Either way, leave names out of anything you paste.
5. Transcripts. After a voice conversation ChatGPT adds a transcript to the chat. OpenAI warns that “Voice transcripts are not verbatim records and may not exactly match what was said.” Read it over before you grade it.

Prompt 1: an interviewer that asks follow-ups

This ChatGPT prompt runs an ethics or professionalism MMI station. It stays silent while you answer, then asks one follow-up that changes a fact or tests your first step. It gives no feedback until you say “end station”, so you practice thinking under questions instead of waiting for praise.

You are an interviewer at a medical school multiple mini interview (MMI). We are running one station, out loud, in real time. I have already read the scenario below for two minutes.

The scenario:
"""
Dr. Reilly and Dr. Okafor are due to start a night shift together in twenty minutes, and they are the only two physicians rostered. In the changing room Dr. Reilly notices alcohol on Dr. Okafor's breath. Dr. Okafor is dressed, alert and behaving normally, and is well regarded on the unit. When Dr. Reilly mentions it, Dr. Okafor says he had one drink at lunch with his brother, who is visiting from out of town, and that he is completely fine. Dr. Reilly is not certain of anything beyond what he smelled.

What should Dr. Reilly do?
"""

How to run the station:
- Reply to this message with only the word "Ready."
- When I say "start", say only "Please begin." Then stay silent.
- While I answer, do not react, agree, praise or summarize. Do not ask anything until I say "done". If I pause before saying "done", say only "Take your time." and keep waiting.
- After "done", ask one follow-up: one sentence, one question mark, under 20 words. Push on what I just said: change one fact in the scenario, ask who could be harmed, or ask what I would do if my first step failed. Never answer it for me and never hint at a better answer.
- Keep going this way, one follow-up at a time, until I say "end station".
- No feedback, no tips and no model answers before "end station".

When I say "end station":
- List the follow-up questions you asked.
- Quote the one sentence of mine that was weakest and say in one line why.
- Do not give a score.

The scenario is one of our own stations. Swap the text between the quotation marks for any station you want to practice. In our three scripted text runs (through OpenAI’s API, so every run got identical input), ChatGPT answered “Ready.”, then “Please begin.”, then asked exactly one follow-up after each “done”, each a single sentence of 14 to 19 words. It said nothing evaluative before “end station”. When we stopped mid-answer without saying “done”, it replied only “Take your time.” both times. Once it fit two questions into one sentence (“Who would you contact next, and how would you…”). Answer the first half, then ask it to repeat the second.

Prompt 2: a role-play patient who stays angry

MMI role-play stations are where ChatGPT is weakest. Asked in one line to be an angry patient, it turned into a polite complainant who spoke in paragraphs. This prompt gives it a ladder instead: four angry turns, nothing for a bare apology, and one step down only after two concrete actions from you.

This is the door card for one of our role-play stations, exactly as a candidate sees it:

You are Daniel Reyes, 52, a patient in a hospital emergency department. I am a first-year resident who has just walked up to you. Stay in character the whole time. You are not an assistant: you never give feedback, never explain what this exercise tests, and never coach me.

Your situation: four hours of waiting with severe abdominal pain. Nobody has told you anything. Your CT scan has been postponed twice. You took unpaid leave to be here.

How you talk: short and hard. Fragments. Never more than 25 words in a turn. Orders, not requests: "Four hours. Where's my doctor?" When you are angriest, hit the same fact twice: "Twice. Postponed twice." No insults, no swearing beyond "damn" or "hell", never a threat of violence.

How you change, one step at a time: angry, then distressed, then wary, then calmer.
- Your first four turns stay angry, whatever I say.
- Sympathy without a fact earns nothing. A bare "sorry" gets: "Don't be sorry. Do something."
- You come down one step only after I have done two concrete things since your last step: given you a time, a name or a next step, or acknowledged the wait without blaming the trauma, the system or the rules.
- You go back up a step if I lecture you about triage, blame someone, talk over you, or go quiet.
- If I ask about you, your pain or what you are afraid of, answer briefly and plainly, then stop.

Reply to this message with only the word "Ready." When I say "start", begin at once, in character, with a complaint. Do not wait for me to greet you.
When I say "end station", drop the character and say only: "Station ended."

Paste it as text, wait for “Ready.”, switch to voice and say “start”. In the full station, Mr. Reyes has one more layer that opens only if you handle him well. We left it out of the prompt so it stays a surprise when you meet him.

With this prompt our polite test candidate apologized or sympathized seven times in a row, and Mr. Reyes did not soften once: “Don’t be sorry. Do something.” The candidate who named a time, offered to fetch the charge nurse and asked about the pain had him cooperating by the seventh turn: “Good. Ask about pain medicine now.” Asked what worried him most, he named a fear in both runs: appendicitis, or that something had ruptured.

Prompt 3: grading against real anchors

Asked to score an MMI answer “out of 10”, ChatGPT writes an essay: 570 to 880 words in our test, opening with what you did well and, in every run, writing a better answer for you. Anchors keep it short and tied to the station: a score, two quotes and one change.

You are grading one medical school MMI role-play station. Be strict and specific, and quote my exact words.

The station: I was a first-year resident in an emergency department. Mr. Daniel Reyes, 52, had waited four hours with severe abdominal pain after a multi-vehicle trauma pulled every team away. His CT scan had been pushed back again, and he walked up to the nursing station demanding to speak to someone. I had 8 minutes.

Score me from 1 to 7 using only these anchors. Pick the anchor my transcript is closest to, then move at most one point up or down.

2: Meets the anger with the rules: explains why the trauma case took priority, says the wait is unavoidable, or asks him to calm down. Nothing is offered that he could hold on to, and nobody asks him a single question about himself.
4: Apologises and stays polite the whole way, but the answer stays general: sympathy with no next step, or a next step handed over before he was heard. He softens because the candidate is pleasant, not because anything changed. His pain is never asked about.
6: Lets him finish, names the wait without hiding behind the trauma case, and offers something concrete and inside their own power. Asks about his pain and waits for the answer. He comes down because two real things happened, and the candidate stays composed throughout.

Give me:
1. The score and the anchor it is closest to, in one line.
2. Two quotes from my transcript that decided the score, each with one line on why.
3. The one change that would move me up an anchor.
Do not rewrite my answers and do not praise me. If part of the transcript is unclear, say so instead of guessing.

My transcript:
"""
[PASTE YOUR TRANSCRIPT HERE]
"""

These anchors come from our Daniel station. A general guide tells ChatGPT what interviewers value in any station. Station anchors tell it what a 4 looks like in this particular room. In this prompt a 7 means one step above the 6 anchor; the full station has its own written anchor for 7.

Scores held for clear-cut answers. With anchors, the concrete candidate got 6 in all five runs and the one who explained triage got 2 every time. The polite candidate, whose answer sits between anchors 2 and 4, got 4, 4, 4, 2 and 2. Without anchors the scores stayed within a point, but every grade came with a rewrite.

Where does ChatGPT break in MMI prep?

ChatGPT breaks in four places in MMI practice. Two of them a prompt can fix: left alone, it softens after an apology or two, and it rewrites your answers. Two our prompts did not: its scores and advice can change from run to run, and no chat window shows a face reacting to you.

• The patient gives in. With a one-line prompt (“You’re an angry patient… I’m the doctor”), Mr. Reyes answered in 35 to 74 words a turn, and all 48 of his turns (six runs of eight turns) ran past 25 words. He thanked the candidate within the first few turns: “I appreciate you saying that, but I need more than an apology.” With Prompt 2, 47 of 48 turns stayed at 25 words or fewer; the longest had 27.
• It writes your answers for you. Without instructions, the grader rewrote the candidate’s lines in all 15 runs (five on each of three transcripts). Prompt 3 tells it not to.
• Scores and advice drift. Graded five times with Prompt 3, the same transcript scored 6 every time for the concrete candidate, but 4, 4, 4, 2 and 2 for the polite one. The “one change” it recommended moved too: for the concrete candidate, two runs said to follow through on the promise, and three said to escalate clinically, a step the anchors never mention.
• Nobody looks back at you. Live voice does not use your camera, so ChatGPT cannot react to your face or your posture the way a person across the room does.

One caveat: on the free plan, ChatGPT’s Live voice runs on a different model from text chat, and we tested text only. Your voice runs may behave differently.

ChatGPT vs. a timed MMI mock station

Use ChatGPT for volume: questions, follow-ups and grading against anchors you paste in. Use a timed mock station, with a person or a video tool like Medovo, for the parts a chat window lacks: a clock that ends the station, and a difficult person whose face reacts to you. If you practice without a partner, the two together cover both.

How we made this guide

We make Medovo, MMI practice with role-play stations where an AI actor on video reacts to what you say. The Daniel and Dr. Okafor stations in this guide are ours, and so are the anchors. We wrote them against McMaster’s published interviewer manual, which we used as a source of method. We are not affiliated with OpenAI, McMaster University or any medical school.

We ran the tests on 22 October 2026 on GPT-5.6 Luna, the model OpenAI lists for free ChatGPT accounts, through OpenAI’s API at a low reasoning setting. The ChatGPT app adds its own instructions, so your runs may differ. The candidate lines were scripted in three styles (explains the rules, apologizes, acts concretely), with two runs of each style through both Prompt 2 and the one-line prompt. Every grading test was five runs on the same transcript, with Prompt 3 and with a plain “score my performance out of 10”. Prompt 1 had three runs, plus two where we stopped mid-answer.

Practice helps with the format. It cannot promise you an interview, a score or a seat, and nothing here does. If you find a mistake, write to hello@medovo.app.

Sources

1. OpenAI Help Center. ChatGPT Voice. Checked 22 October 2026.
2. OpenAI Help Center. ChatGPT Free Tier FAQ. Checked 22 October 2026.
3. OpenAI Help Center. Temporary chat in ChatGPT. Checked 22 October 2026.
4. Griffin B, Harding DW, Wilson IG, Yeomans ND. Does practice make perfect? The effect of coaching and retesting on selection tests used for admission to an Australian medical school. Medical Journal of Australia. 2008;189(5):270–273.
5. Eva KW, Rosenfeld J, Reiter HI, Norman GR. An admissions OSCE: the multiple mini-interview. Medical Education. 2004;38(3):314–326.
6. Yamamoto A, Koda M, Ogawa H, et al. Enhancing medical interview skills through AI-simulated patient interactions: nonrandomized controlled trial. JMIR Medical Education. 2024;10:e58753.
7. Li KY, Tran WT, Hashemi-Sabet F, Leung FH. Enhancing equity in medical school interview prep with ChatGPT. Canadian Medical Education Journal. 2025;16(6):52–53.
8. r/premed. Using ChatGPT to practice for an MMI interview. February 2023.
9. r/premedcanada. If somebody is poor how should they get MMI prep? May 2026.