Of course. They're called expert systems [1]. Yesterday on HN someone posted a link to a book [2] on probabilistic models of cognition which includes a section [3] on medical diagnosis.

[1] http://en.wikipedia.org/wiki/Expert_system [2] https://probmods.org/ [3] https://probmods.org/conditioning.html#example-causal-infere...

For coders - Peter Norvig's PAIP (which might be The Best Programming Book, but no room to get into that here) talks about these and leads you through building something like EMYCIN, the base of a functioning expert system without anything particularly domain-specific.

But Norvig also put them in context, and left me with the impression that Expert Systems were proven inferior to Bayesian approaches for a lot of the problems they had been developed for.

I can well imagine, though, that there are problems where expert systems are a good fit.

As an interaction model and as a way of guiding control flow, as a weird and different way of handling user interaction and building extensible applications, I think the EMYCIN example from PAIP is pretty cool. I've wondered how possible it could be to use something like EMYCIN to write webapps ...

We should get in touch, I've started translating Mycin into CoffeeScript, with the hopes of creating a crowdsourced medical expert system within the summer.

This sounds very cool. If you're planning on open sourcing any and all of this I'd like to contribute

Yes, it will be open sourced! I want to show engineers just how inanely dumb some of the algorithms in medicine are, and how (I believe) we can start creating publicly usable algorithms to pipe knowledge to the consumers once they get access to a bunch of data from consumer medical devices. Lofty goals, but I will attempt to execute on the idea!

Thanks Rob! Would love for you to participate and help me iterate once I release a prototype in a week or two. I have a colleague at Weill Cornell who may help test drive the system as well. Got your email in my notebook!

as a (new) doctor I would love to help out if I can as well

I think it was "author's certificate", also called a "inventor's certificate". It didn't give the author the right to exclusively use the invention. There were no exclusive patents in the Soviet Union, if I recall correctly.

http://en.wikipedia.org/wiki/Glossary_of_patent_law_terms#Au...

Hope I remember it correctly, a story form couple years ago about students form some polish university (was it PUT?) working on such system. It was meant to be only an assist to a doctor, because legally it was all it could ever be...

Anyway, the students loaded the system with rules from literature, interviews, etc and the testing started. Soon it was clear that there was mismatch between what system suggested and what doctors diagnosed. Not always but more than expected. The rules were updated and it was a bit better, but still not there. After some back and forth finally the doctors were told to speak aloud about what they are doing examining the patients - and it become clear that doctors used additional criteria, not mentioned in the interviews (when directly asked about that stuff). And even then it was not enough to explain the differences! Simply the doctors were using additional rules that they themeself were not fully aware they were using.

Sadly I don't know what happened to that project or any more details but the implications from this story always make me think... even highly trained individuals using very strict and well defined decision process end up with result that they can't fully explain! What if we could make this hidden expertize explicit to better train future doctors or just check if it is even valid?

This is really interesting, do you have a link to the article?

I heard about it from people working on that project, it was hour long presentation but this single anecdote is all I remember from it after 9(?) years...

You might be interested in http://en.wikipedia.org/wiki/Decision_tree_learning

(Wikipedia makes it sound very complex, but you can do decision tree learning from hand from tabulated data easily, it is just tedious)

I can see how a decision tree with 2 layers may be possible, but once it gets to 4/5 layers, I think the conditional information would be very hard to keep track. It's like looking at a heat/k map at 5 dimensions, it gets really taxing.

Huuuuge problem is reconciling the hundreds of DSLs physicians use to talk about different things--you'd think that they'd use the same terms to talk about the same body parts and diseases, but you'd think wrong. :(

There is lots of software for decision analysis style decision trees. See: https://www.informs.org/ORMS-Today/Public-Articles/October-V...

There is currently some confusion about decision trees used in decision analysis because the term "decision trees" is also used in machine learning but the approach is unrelated to decision analysis.

Yeah, of course. There are general tools like the ones mentioned here and also the entire field of health informatics and medical decision systems. It's a very well-developed field, but there are lots of social issues which prevent the widespread use.

> patent - why would someone do that?

It's usually to protect their idea, so they can use it in a product or business venture. There's some good information on patents and the way they are used on Wikipedia.