Thursday, April 25, 2019

Record Location Services at a National Scale using IHE XCPD

One of the recent discussions coming up around the most recent TEFCA related specifications has to do with how one might implement record location services for patients at a national scale.  The basis for this is the IHE Cross Community Patient Discovery Profile (XCPD).

Here's the problem in a nutshell.  Assume you are a healthcare provider seeing a patient for the first time, and you want to find who else might have information about this patient?  How can you do so?

The first step obviously is to ask the patient who their prior doctor was, and here's where the first fundamental challenge appears.  Sometimes the patient is unable to answer that question, either at all, or at least completely.  So, then, how do you get a complete list?  What you don't want to do is ask everyone who ever might have seen the patient anywhere in the country, because that is not going to scale.

I think that about sums it up.

The IHE XCPD profile is designed to address this.

If the patient is only able to give a partial response, then you know where to start looking.  Here's the key point, once you know where to start looking, the organizations and networks who can answer the question can also point you to others who've seen the patient, and that can get you a more complete list, which eventually will lead to closure.

But wait! How do these organizations know who else has seen the patient?  It's really pretty simple.  Somebody asked them, and in the process of asking them, also told them that they would be seeing the patient, and so the original provider gains the information about the new provider seeing them, which makes them able to answer the question accurately for the next new provider.  And so the well known provider becomes more authoritative, while the new provider is able to provide equally authoritative data.

If the patient is unable to answer that question at all, then you have to figure out who else you might be able to ask that question of.  If the patient is local, you could ask others in the area who might know the patient.  If the patient isn't local (e.g., just visiting), you might try asking others near to where patient resides, which hopefully you can determine.  Since TEFCA is about a network of networks, it's reasonable to assume that there are some regional networks of whom you might ask about a given patient, and they might be able to ask other, smaller regional networks they know about (this could become turtles all the way down, but at some point, you'd expect to stop).

There are some other issues to address.  Just because we got the new provider and the old provider synchronized, doesn't mean everyone else is.  Who has that responsibility?  That's an implementation decision.  It could be the original provider, or it could be the new provider.  Since the new provider is gaining the benefit, one could argue it's there responsibility to notify other networks that have already seen the patient that they are now seeing the patient.  That would be the way I'd implement it.

Note: This doesn't have to be perfect.  It has to be good enough to work.  Perfecting the algorithm for record location to ensure the right balance of performance and accuracy in the RLS is going to take time.  But we can certainly build something that gets the right networks talking to each other.


  1. Keith - this is so retro of you. :)

    How about we try a new paradigm. What if every patient had their records and could share them with their provider?

    How about if they could share their data with anyone else they trusted - their family caregiver maybe or who knows maybe even shop around a bit or do other socially positive things like share their data for clinical research purposes?

    Rather then playing a game of seek and seek - what if maybe we eliminated the reliance on a network and some partial satisfactory software attempts devised before individuals cared computing capacity in their pockets and actually give the consumers their data and expect the docs to take the data from the patient rather then setting up the industry for another lock-in network teselated monopoly?

    I don't know - just saying.

    Love you bro.


    1. Dude, when APIs are available with my provider's I'll be among the first adopters, and will do what I can to have my records. But I picked my provider for the fact that I knew I'd be able to get my data from them. Mom didn't have a choice about where to go when she had her heart attack, and would rather pick a good doctor than one who is up on all the latest and greatest tech stack (even if I helped create it). So, I might be retro about XCPD, but I can tell you it's a heck of a lot less retro than the solutions that most patients have today (paper and fax).

      As for partially satisfactory attempts ..., if we waited for perfect for solutions, we still wouldn't have e-mail.