PatientSim is a research framework for simulating realistic emergency department doctor–patient interactions, presented at NeurIPS 2025 (Datasets & Benchmarks).
Large language models act as patients with controllable personas — you choose their personality, language proficiency, medical history recall, and cognitive state — producing diverse and realistic consultation scenarios for training and evaluation.
| Mode | Description |
|---|---|
| 🤖 Auto Simulation | Watch an AI doctor conduct a full consultation with the simulated patient and arrive at a differential diagnosis — no input required. |
| 🩺 Practice Mode | You play the doctor. Consult the simulated patient, gather medical history, and work toward a diagnosis yourself. |
Configure your session below. Select the patient case you want to simulate, choose the AI model to power the patient, and define the patient's persona across four behavioral axes. When ready, click Start Simulation.
🔑 Model & API Key
This demo runs on a shared API key with a limited number of free calls. If the free quota has been exhausted, please enter your own API key below (OpenAI or Google Gemini) to continue without restrictions. Your key is used only for this session and is never stored on our servers.
Your patient agent is ready. Review your configuration below, then pick a mode. Auto Simulation runs a fully automated consultation so you can observe the system in action. Practice Mode puts you in the doctor's seat for hands-on training.
Watch a fully automated consultation between an AI doctor and the simulated patient. The doctor conducts the interview and arrives at a differential diagnosis — no input required.
You play the doctor. Choose how much patient information to display on the side panel.
An AI doctor is conducting the consultation. The doctor will ask questions, gather medical history, and conclude with a differential diagnosis. Doctor messages appear on the right; Patient responses on the left.
You are the attending physician. Type your questions and responses in the box below to consult the simulated patient. Use the patient profile panel on the left for reference. Try to gather sufficient history to reach a differential diagnosis.