> For the complete documentation index, see [llms.txt](https://prep.pathcheck.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://prep.pathcheck.org/privacy-preserved-ai-for-healthcare/multi-party-computation.md).

# Secure Multi-Party Computation

![](/files/-MZ4H3VOZTm01tD6OhYs)

Let's look at the third method, which is secure MPC. Imagine Jane wants to know how many phones are reporting fever. John sending “one”  means he has a fever and “zero” means he does not. To do this, John’s phone sends “70” to server P on the left and the number “minus 69'' to server Q on the right. Of course, 70 minus 69 is one. The second phone sends 38 and -37. Third sends 42 and -42. The Left server adds up to 150, and the right server to -148. And that leads to the answer 2 people with fever which Jane sees without knowing about John or his fever status.

The goal behind using secure MPC in our toolkit is to **facilitate anonymous symptoms reporting** by the public, without compromising their individual privacy.

{% embed url="<https://en.wikipedia.org/wiki/Secure_multi-party_computation>" %}

{% embed url="<https://crypto.stanford.edu/prio/>" %}


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://prep.pathcheck.org/privacy-preserved-ai-for-healthcare/multi-party-computation.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.