Tuesday, January 29, 2013

Wednesday, January 16, 2013

An Ontologist's Guide to HL7

A talk under this heading was presented as part of the National Center for Biomedical Ontology seminar series. Slides and a recording of the talk are available here:

http://www.bioontology.org/ontologist's-guide-to-HL7


Wednesday, January 02, 2013

The RIM of Despond


Looking Back

In the more than 7 years since HL7 Watch was founded in 2005, we have drawn attention to a number of deep flaws in the structure of the RIM. Examples of such flaws are:

1. No coherent distinction between an observation and what it is on the side of the patient that has been observed.
See The Multiple Joys of HL7 V3

2. No coherent treatment of the relation between an act of observation and the statement, assertion, or datum (for instance a measurement result) that is the result of this act.
See The Weight of the Baby

3. No coherent distinction between an act and the record of an act. 
See Still An Incoherent Standard

4. No coherent way within the framework of the RIM to track how concerns (for example diseases) in a single patient evolve with time.
See Still no coherent way to track concerns

5. No coherent way of distinguishing between condition (an enduring entity) and act (an event taking place at a time). (References to the 'condition of the patient' do indeed appear in HL7 standards documents, but the term 'condition' is nowhere defined – because it cannot be defined in conformance to the RIM.)
See Diseases as dependent continuants

5. No coherent distinction between intentional acts (for instance ordering, prescribing) and events in general (for instance accidental falls, events within the interior of the patient's body).
See HL7 and SNOMED CT

6. No coherent way of dealing with what the RIM calls 'effective time'.
See: Still confusion after 14 years

We have repeatedly pointed to the ways in which these flaws cause problems in learnability and teachability,  and thus in usability and codability, of HL7 v3-based standards. We have also averted to the way in which these problems re-appear with each new generation of coders and business analysts charged with working with HL7 v3, as evidenced most recently by the email threads we cite below.

Where We Stand Today

HL7 v3 remains an incoherent standard. Indeed as we have shown in  a recent paper (in press), matters are in this respect getting worse. The paper, which is entitled "Human Action in the Healthcare Domain", reviews the recent 'Release 4" of the RIM ballot document ISO/HL7 21731:2011(E), referred to in what follows as ISO RIM Release 4. This doctrine contains a series of welcome attempts on the part of the HL7 community to add clarity to their earlier publications, and it also contains a number of attempts to add ontology-like components to the HL7 structure. Unfortunately, however, these new additions do not replace the earlier, incoherent portions of the RIM specifications.  Rather, they are simply added on to the existing formulations, with no attempt (as far as we can see) to secure any sort of logical consistency.

Because, astonishingly, the RIM's basic flaws have in this way been significantly magnified, the result will be further waves of instability in the v3 standards. Because the needed changes will be made by different specialist groups, new inconsistencies will arise, which will be resolved, where they are resolved at all, by ballot, rather than by logic. The prognosis for the future of HL7 is not good.

Matters are made still worse as a consequence of the inclusion of CDA/CCD – with their HL7 legacy elements – in the Meaningful Use standards. We can anticipate that the cries for help from within the HL7 and associated vendor communities will become even louder. First examples are already here:

From: owner-strucdoc@lists.hl7.org [mailto:owner-strucdoc@lists.hl7.org] On
Behalf Of Kumara Prathipati
Sent: Mon 12/24/2012 10:40 PM
Subject: CCD DESIGN - VERY COMPLEX

Hello,

I was trying to understand allergies section CCD examples. It is very interesting the way CCD was designed to state "No known drug allergies".  It is just mind boggling how complex and complicated the CCD design was.

Just to say  "Pt has no known drug allergies' takes 25 lines of CCD. This tells us how inefficient this system has grown to be till now. [25] lines to tell 1 sentence "Patient has no drug allergies" (http://motorcycleguy.blogspot.com/2012/03/how-to-say-no-med-allergies-in.html).

... It is beyond my comprehension how this whole process ended up this complex. (looks like too late to change direction). If it needs a PhD to understand CCD, time to think again and  commit to design a more simple system even if it takes a lot of effort..

Any one who is responsible to create a piece of software to generate CCD or import CCD has to spend his life time understanding. He has to attend many courses given by experts and spend thousands of dollars.

I looked at NCPODP XML representation of ERx which looks a 100 time more simple than CDD and any one can understand in a few hours (including myself who went thru it). Hats off to NCPDP experts who made it so easy any one can understand in less than 1 day.

Looks like the current CCD experts are unable (unwilling since it is too late) to make this a simple but equally effective system to meet 95% of requirements. Your are increasing the cost of creating the interoperability modules for EMR products and HIEs. Still the medical community is not using CCD on a wide scale which is a result of the complex system designed by experts. I do not believe it is not possible to design a system 1/2 as complex. I hear the same response "the requirements are complex and so the system is complex".  I disagree with this statement ...

If CCD becomes very complex and expensive to implement, it will become  a disaster in health care because the whole clincial data exchange depends on this.

I see endless discussions on the element . If it takes so much discussion, the elements are named vaguely and time to junk that element or rename it. Many elements have poor naming systems. It takes some times hours of Google search to understand the meaning of your CCD XML elements and attributes. XML is supposed to have self explanatory elements and attributes. This is missing in in many of elements.

Just to give an example of poor element/answer naming. When I see "code=ASERTION". Just makes no meaning  at all to me. Concept is vaguely explained after extensive Google search.

... I am a practicing physician for 30 years and documenting allergy information for 30 years , almost daily. It's unbelievable frustration to digest your CCD manuals.

Kumara Prathipati MD

---

More examples of such cries for help (and associated general confusion) are provided in the email threads below, which are taken from the HL7 Strucdoc Digest of December 29, 2012. For the sake of readability, I have removed repetition and some digressions, and associated emails on a single topic in chronological order. Notes in yellow are from myself ([BS]) and Bill Hogan ([WH]).

Thread 1: Confusions regarding Observation.Code and Observation.Value

From: owner-strucdoc@lists.hl7.org [mailto:owner-strucdoc@lists.hl7.org] On
Behalf Of Kumara Prathipati
Sent: Thursday, December 27, 2012 12:19 PM
Subject: Re: ALLERGY SECTION QUESTION

Brian,

To help many many thousands of coders and business analysts working in EHR, HIE companies we have to make this simple, simple and more simple.

I will  explain like this


  Observation/Code = question

  Observation/Value = answer


some times answer does not  require a question (then you can use nullflavor).  This happens when answer is self explanatory.

Examples


  Observation/code = manifestation

  Observation/value = skin rash


  Observation/Code = Temperature

  Observation/Value = 99.8


Every observation must have /code and /value


  Observation/Code = wound depth

  Observation/value = 2.2 cm


  Observation/Code = heart murmur

  Observation/value = absent


I can [give] a 1,000 examples applicable in health care. I see no need to explain in 10 sentences but need to give 20 examples. Then no one has to attend courses to understand. Any one can implement CCD/CDA.

For heavens sake, at least give lot of examples with various clinical situations. EXISTING SYSTEM IS TOO COMPLEX, COMPLICATED, CONFUSING, FRUSTRATING ...

Kumara

---

From: owner-strucdoc@lists.hl7.org [mailto:owner-strucdoc@lists.hl7.org] On
Behalf Of Brian Zvi Weiss
Sent: Thursday, December 27, 2012 4:44 PM
Subject: RE:
Kumara,

If I understand you correctly, the case you are making for the code/value of an observation being a question/answer with "code" always being present (or nullflavor),  is really more an argument about what SHOULD be the case in your view, rather than what IS the case. Correct?

The white paper from the Terminfo project talks to the role of code in the RIM as being "the action taken in making the observation".  It jumps through a lot of hoops to even justify "Body Weight" being a "code":

This example is not in line with strict interpretation of the formal RIM definition in which the Observation.code is the action taken to make the observation. However, it is a more familiar form in real-world clinical statements about many observations. A possible bridge between these two views is to regard the name of the property observed (i.e. "body weight") as implying the action to measure or observe that property.

So, the definition of "code" becomes "action of observing or the property observed" - and for situations where you don't have either of those, ASSERTION (not a nullflavor) is used for "code".

[BS:] This tells us how deep is the confusion in HL7 circles as to what is meant by 'code'.

I'm not saying those were good decisions or arguing with you that we wouldn't be better off with what you recommended below.

But I do think it's important that we keep separate:

1. "support" questions about how the standard is to be implemented (resolving ambiguity, establishing best practice, need for more examples, etc.).

2.  questions/challenges on the standard itself (that have to be addressed in future versions and other standards creation work)

I'm still not 100% clear if this listserv is the place for both of those agendas - I think it is.  Either way, it has to be clear to all when we are involved in a discussion about #1 and when about #2.

So, if we limit ourselves to #1 for a moment on this topic, I don't think your explanation works because it doesn't seem aligned with what the C-CDA spec requires.  The C-CDA spec is clear on where ASSERTION has to be used ... and other guidance on what values or value sets are legitimate for "code" in other templates.  ...

Brian

---

From: Mead Walker [mailto:dmead@comcast.net]
Sent: Thursday, December 27, 2012 19:36
Subject: RE: ALLERGY SECTION QUESTION

Hello Kumara,

I think your suggestion of illustrating points of possible confusion with examples is a great one.

However, it does seem one of your examples sits on the minority side of a much earlier debate about the use of code and value. Namely,


Observation/Code = heart murmur

Observation/value = absent


I think the more conventional approach would be:


Observation/Code = ASSERTION

Observation/value = heart murmur


By the way, I have always thought that one of the drivers behind this was
the desire to identify preferred code systems for observation code (LOINC)
and observation value (SNOMED and others (although hopefully only SNOMED to
some))

Mead

[BS] Compare the earlier debate in ontology circles as concerns an effective avenue for ensuring consistency as between 'Attribute' and 'Value', where some, for example, regard 'Color' as Attribute and 'Red' as Value, others regard 'Red' as Attribute, 'Dark' as Value. The solution proposed involves the imposition of a single hierarchy, whereby all values are seen as is_a children (subtypes) of the corresponding codes (values for codes at one level can be codes themselves for values at a lower level). Thus for example

Color
Red 
Dark

Manifestation
Skin rash manifestation
Severe skin rash manifestation

Temperature
        99.8 degree Celsius temperature 

Wound depth
        2.2 cm wound depth

Observation for potential heart murmur
Observation for potential heart murmur with result: negative

For the general idea, see the discussion of the EQ method in Nicole L. Washington, Melissa A. Haendel, Christopher J. Mungall, Michael Ashburner, Monte Westerfield, and Suzanna E. Lewis, "Linking Human Diseases to Animal Models Using Ontology-Based Phenotype Annotation", PLoS Biolology 2009 November; 7(11): e1000247. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2774506/

----

Thread 2: Assertions and Observations

From: owner-strucdoc@lists.hl7.org [mailto:owner-strucdoc@lists.hl7.org] On
Behalf Of Lisa Nelson
Sent: Friday, December 28, 2012 01:52
Subject: RE:

Brian,

I thank you for bringing up both this issue about the use of "Assertion" in the code element of an observation and the syntactical issue of the outer Problem Concern Act that can group several Problem Observations into a single Problem Concern.

I have been very concerned about the use of "Assertion" in the observation templates you have identified and several others too. (Check out some of the Problem Observation examples on page 442 of the C-CDA IG. They show the use of "Assertion" as the observation/code/@code even though the value set established for the code element does not include "Assertion" as one of the value set codes.)  Also, my experience testing CDA Documents for Connectathon has revealed that vendors do not adequately represent Problem Concerns in the narrative text of a Problem Section.  They are revealing a "structured representation" of the machine readable entries which does not show, in a humanly readable way, the relationship of the outer Problem Concern which wraps the Problem Observations.  Vendors just aren't getting this (in my opinion).

I think it is very important to examine the impact and rationale for using "Assertion" and further delve into the Problem Concern Act and what it's use implies for implementations. Now that we are beginning to get some real implementation experience, I think we should step back and see if we truly understand the impact of our earlier design choices, in order to confirm if they all still make sense or not.

... I think it is time we clearly understand what this decision implies for the practical use cases of the data.  I would not be at all surprised if something that we thought made sense a couple of years ago, turns out not to be a good idea, now that we see the implications for implementation.  I think this topic about the use of assertion and the other topic about the use of the outer Concern Act need to be carefully scrutinized to make sure our implementation guidance makes sense in light of what we are envisioning for quality measures which are highly dependent on being able to identify problems in a patient's record. Now that we have  a clearer picture about how Quality Measures are specified (HQMF) and how patient-level quality documents are created (QRDA), I think we need to make sure that our implementation guidance for recording problems, lines up with the envisioned future uses of the information. ...

Regards,

Lisa

----

From: owner-strucdoc@lists.hl7.org [mailto:owner-strucdoc@lists.hl7.org] On
Behalf Of Brian Zvi Weiss
Sent: Friday, December 28, 2012 5:05 AM
Subject: Considering Changes in ASSERTION and nesting of Problem and Allergy Concern Acts

Thanks, Lisa.  ... I think we have to be very careful here when it comes to how we approach evolving the standard, now that it is baked into MU2 and the "train has left the station" on that.

In my thread yesterday with Bob re. my expectations for active "disambiguation"  of the spec by HL7, my assumption was that we were looking to create additional constraints that would further refine the ones we already have in order  to eliminate ambiguity in the implementation of those existing constraints - but without changing the existing constraints.

But here you are (as Kumara was earlier) referring to potentially substantively changing the spec.  I'm not arguing the correctness of your recommendations - they make sense.  But as in my earlier comments to Kumara, I think we need to be very careful to keep separate the issue of "how the spec should change/evolve" from "support infrastructure".  Really there are three categories here:

1)  Support infrastructure for answering questions that don't have implications for changes in the spec

2) Resolution of ambiguities via additional constraints (what Josh terms "best practices") being added to the spec (initially as "best practice guidance" and then working their way into the next release of the spec)

3) Evolution of the spec itself to change how things are done (creating new constraints that contradict the previous ones)

... In #1, I think the key issue is to what level HL7 wants to be involved here, the business model for funding it (e.g. membership only), the resulting SLA and infrastructure, etc.

 In #2, I think the key issues are:

A.  What is the right way to handle the process in both an authoritative and timely way, given that the cycle for full revisions of a spec and all the associated process for attaining consensus via balloting, etc. is too slow and we can't leave so many fundamental ambiguities out there for the market to sort out one pairwise integration at a time.

B. What is the commitment level of HL7 to focusing on this agenda rather than just "moving on" to the next version of the spec, other standards, etc. and the infrastructure for making it work

In #3 I think the key issue is what the rules of the road are once the train has left the station, as I noted above.  MU2 rules are working their way into certification testing infrastructure and are actively being worked on by vendors who have high levels of pressure and urgency to get their products "MU2 certified" quickly.  The implications of changing up the rules on them midstream is worrying.

... Of course at the end of the day, as you noted, we shouldn't have to live forever with a significant mistake (from a practical implementation perspective) once we've identified it.  Just saying it's tougher to navigate the whole issue of backwards compatibility when a particular release takes on a life of its own as part of something like MU.  I think it would be a something of a nightmare if the latest C-CDA spec was not consistent with what was being tested (or planned to be tested soon) for the latest (or upcoming) MU certification round.

So I would caution us re. the "enemy of 'good enough' being 'perfect' ".  As long as we disambiguate and provide enough examples, the market will manage through the stuff that has us now scratching our head and asking "how did we end up with this strange construct".  Not ideal, but probably not tragic - as long as there is a clear, single, right way to create/interpret the information and it is possible to get in the data into the document.  The time may have passed for "doing it better".

---

From: Lisa Nelson [mailto:LisaRNelson@cox.net]
Sent: Friday, December 28, 2012 6:08 AM
Subject: RE: Considering Changes in ASSERTION and nesting of Problem and
Allergy Concern Acts

Brian,

... I agree with the sentiment that you have expressed. We need to find a way to work on this plane while we are flying it.  ...

I believe we can do it.  We need to do the disambiguation, develop the examples, and then release clarified guidance (which could involve adding some additional constraints) in a way that doesn't break everything we have already put in place.  I think that template versioning plays a key role in developing the ability to do this, which is why I'm focusing there first. Once we have clearly defined how to do versioning, then we will have the mechanism to release, for example, a new Problem Observation  or Problem Concern Act template which is a new version of the existing template but includes the revisions which we determine will add the needed clarity without breaking our prior constraint assumptions.  It is a tricky puzzle to solve, but I'm certain it can be done.  ...

Lisa

Lisa R. Nelson, MS, MBA | Consultant | Life Over Time Solutons | cell:
401.219.1165 | Westerly, RI | LisaRNelson@cox.net

---

From: owner-vocab@lists.hl7.org [mailto:owner-vocab@lists.hl7.org] On Behalf Of W. Ted Klein
Sent: Friday, December 28, 2012 8:54 AM
Subject: Re: HITSP value set stewardship

... I am concerned because questions about Quality Measures keep coming up around the vocabulary, and I don't know of any authoritative sources of truth for the sets of codes to be used, and in some cases even the identifier of the value set to be used.  This whole thing resembles some kind of hot potato that no one wants to hold on to for very long.

Ted

----

From James T. Case
James T. Case MS, DVM, PhD, FHL7, FACMI
Health Program Specialist, SNOMED CT
National Library of Medicine, National Institutes of Health
On Dec 28, 2012, at 10:35 AM, "Case, James (NIH/NLM) [E]" wrote:

Ted,

As far as I am aware, all of the value sets that were identified for the approved eMeasures for MU stage 2 are available from VSAC (https://vsac.nlm.nih.gov).  You would be well advised to point those that have vocabulary questions to that site.  The VSAC is the “source of truth†for all of these measure value sets.

Jim

---

From: owner-strucdoc@lists.hl7.org [mailto:owner-strucdoc@lists.hl7.org] On
Behalf Of Brian Zvi Weiss
Sent: Thursday, December 27, 2012 12:41 PM
Subject: RE: ALLERGY SECTION QUESTION

Josh,

...  Sounds pretty compelling - would be curious if anyone on this list wants to make the case for a counter-argument that multiple observations within a concern act (allergies and/or problems) should be used?

Does the best practice place any value on the concern act at all?   As per Gaby's note, the effectiveTime data range in the concern act adds no value if C-CDA says it has to be the same as that in the observation (BTW, where does it say that? I tried to find that in the C-CDA IG but didn't see it?). The concern act status doesn't seem to add value, only confusion if it contradicts the observation status.

So, is the best practice just to consider the concern act "wrapper overhead" and create it to spec when creating the C-CDA and ignore it on interpretation of a received C-CDA?

Brian

---

Thread 3: Continuing Confusions about Effective Time

From: Brian Zvi Weiss [mailto:brianzviweiss@gmail.com]
Sent: Thursday, December 27, 2012 1:06 PM
Subject: RE: ALLERGY SECTION QUESTION

... So, it sounds like there isn't consensus on the best practice here that Josh is recommending (limiting concern to a single observation).  Various questions in my mind (like how the example you gave would work given the limitation Gaby and Josh noted on the effectiveTime in the concern and the observations - though also not sure where in the IG it says that) but I'm out of my depth here.  My boundary ends with "understanding what is in the standard" (trying to do that) not discussing "what should be in the standard".  So, I'll leave that to you, Josh, and others.

As always, I would just encourage us to not leave this hanging and try to come to some kind of authoritative guidance.  This is another example of  where the spec alone isn't enough (as "the whole problem list in a single concern" is syntactically valid, there is debate on the best practice recommendation, etc.).  I'm happy to assist in writing up the conclusions. But can't help in deciding what that conclusion should be.

Brian

---

From: Bob Dolin [mailto:bob.dolin@lantanagroup.com]
Sent: Thursday, December 27, 2012 22:49
Subject: RE: ALLERGY SECTION QUESTION

Hi Brian,

... Think of the concern act as corresponding to an item on a problem list. Pretty much every EHR I've seen allows you to make sequential updates to a problem - e.g. today you might call it "chest pain", next week, after further study, you might update it to "esophagitis". I acknowledge that more guidance would help.

To Josh's point, the rationale for multiple observations in a Concern wasn't to allow you to put the whole problem list in a single Concern, but rather to allow you to track the course of a problem over time.

Bob

---

From: Bob Dolin [mailto:bob.dolin@lantanagroup.com]
Sent: Thursday, December 27, 2012 23:26
Subject: RE: ALLERGY SECTION QUESTION

Hi Brian,

Where a concern has multiple observations - consider an EHR, where a clinician updates an item on the problem list, then updates that item again at a later date. Typically, the most recent observation would be displayed by the EHR, with the other observations retained for historic reference.

As for "authoritative guidance" - this is tricky. Imagine for instance, we create a standard that has an ambiguity (I interpret it one way, you interpret it another way). We then issue "authoritative guidance" that says to do it the way you've interpreted it. Would you then find instances based on the way I interpret it to be non-conformant? Historically, Structured Documents has issued "internal working documents" [http://wiki.hl7.org/index.php?title=Structured_Documents_Internal_Working_Documents]. ...

Bob

---

Subject: effectiveTime in Problem Concern Act and nested Problem Observations (and effectiveTime in Allergy Concern Act)
From: "Brian Zvi Weiss"
Date: Fri, 28 Dec 2012 10:18:55 +0200

Bob,

Where a concern has multiple observations - consider an EHR, where a clinician updates an item on the problem list, then updates that item again at a later date. Typically, the most recent observation would be displayed by the EHR, with the other observations retained for historic reference.

Can you explain how effectiveTime should be used in the problem concern act you described (item on the problem list updated several times and the other observations retained for historic reference)?  Ideal would be an example C-CDA snippet demonstrating this.
 


[WH]  Here we see ongoing and persistent confusion about what effectiveTime is for.


From what Josh and Gaby wrote there seems to be an understanding that the effectiveTime should be the same for all observations in the same act and for the act itself.  I can't yet figure out where it says this in the C-CDA spec - I think Josh indicated this was implied by the guidance to use "onset date" for the lower bound of the effectiveTime and Gaby seemed to suggest it was an explicit requirement that the act and observation effectiveTime match.  All I saw for Problems was the following in the Problem Act:

The effectiveTime element records the starting and ending times during which the concern was active on the Problem List.

And the following for the problem observation:

This field [low] represents the onset date.  This field [high] represents the resolution date.  If the problem is known to be resolved, but the date of resolution is not known, then the high element SHALL be present, and the nullFlavor attribute SHALL be set to 'UNK'. Therefore, the existence of a high element within a problem does indicate that the problem has been resolved.

But assuming Gaby and Josh are correct, those constraints they indicate don't seem consistent with the scenario you are describing whereby the whole point of having multiple observations in an act is to track the historical evolution of the concern as the observations change?

I'm trying to get to the bottom of this. a concrete example would help out a lot here!

Once that is clear, I'd also like to understand the difference in how effectiveTime works in Problems and in Allergies.  The guidance on the Allergy Concern Act is:

If statusCode="active" Active, then effectiveTime SHALL contain [1..1] low.
If statusCode="completed" Completed, then effectiveTime SHALL contain [1..1]
high

and there is no effectiveTime on the allergy problem observation(s) contained inside the allergy concern act.

Brian

[BS] From the ISO RIM Release 4 document we learn that  


Act.effectiveTime =Def. The clinically or operationally relevant time of an act, exclusive of administrative activity.

In the associated Usage Notes we are told that 'The effectiveTime is also known as ... the "biologically relevant time" (HL7 v2.x).' The first example provided is then: 'For clinical Observations, the effectiveTime is the time at which the observation holds (is effective) for the patient.'  Unfortunately, the effectiveTime in this example is not the 'relevant time of an act', rather it is the relevant time of a condition on the side of the patient. For  a clinical observation such as 'staph aureus infection detected' the effectiveTime (as "biologically relevant time") would start when the corresponding condition first begins to exist in the patient. But because the RIM has no place for conditions in the patient, but rather only for observations of conditions, the RIM has no means to formulate this understanding clearly. The result are the repeated flare-ups on HL7 discussion lists where ever new parties complain that they do not understand what is meant by 'effectiveTime'.

As the reader can easily ascertain, the further examples of correct usage of 'effectiveTime' in the ISO Release 4 document do not, unfortunately, resolve the confusion.

---

From: owner-strucdoc@lists.hl7.org [mailto:owner-strucdoc@lists.hl7.org] On
Behalf Of Brian Zvi Weiss
Sent: Friday, December 28, 2012 10:19
Subject: effectiveTime in Problem Concern Act and nested Problem
Observations (and effectiveTime in Allergy Concern Act)

Bob,

Where a concern has multiple observations - consider an EHR, where a clinician updates an item on the problem list, then updates that item again at a later date. Typically, the most recent observation would be displayed by the EHR, with the other observations retained for historic reference.

Can you explain how effectiveTime should be used in the problem concern act you described (item on the problem list updated several times and the other observations retained for historic reference)?  Ideal would be an example C-CDA snippet demonstrating this.

---

Subject: statusCode in Problem Concern Act and nested Problem Observations (and Allergy Concern Act / Observation)
From: "Brian Zvi Weiss" Date: Fri, 28 Dec 2012 11:26:56 +0200

Bob,

....  In this mail I want to focus on status values.  Again, let's start with Problems and then we'll go to Allergies.

The Problem Concern Act has a status code where the value set is listed as 2.16.840.1.113883.11.20.9.19 (ProblemAct statusCode) - which means the following choice of values (as per Table 124: ProblemAct statusCode Value Set): active, suspended, aborted, completed.

The Problem Observation status code comes from the same code system as above
(2.16.840.1.113883.5.14 HL7 ActStatus) and is set to a fixed value of "completed".  Nested inside the Problem Observation is (optionally, 0..1) a single Problem Status, whose value attribute comes from the value set HITSPProblemStatus 2.16.840.1.113883.3.88.12.80.68 which is part of SNOMED.  The values there are: active, inactive, resolved.

So.

1)      What is the precise meaning of the status in the status code of the Concern Act?

2)      What is the precise meaning of the status in the Problem Status value inside the Problem Observation(s) inside the Concern Act?

3)      What rules, if any, govern the relationship between the status of the Act and that of the Observation it contains (in the case of a single Observation)?

4)      What rules, if any, govern the relationship between the status in the Problem Status value inside the Problem Observations when there are multiple Observations inside a single Concern Act?  Does the case of multiple Observations change the previous answer in #3 re. relationship of status in Concern Act and status in Observations (plural)?

5)      How are status changes of an Observation managed within a Concern Act?  Are you supposed to have multiple Observations indicating the evolution of the Observation within the Concern, or just replace status of the Observation with the new status?

In terms of Allergies, the status codes match up with Problems - the concern act uses a status from 2.16.840.1.113883.11.20.9.19 (ProblemAct statusCode) and the Allergy Intolerance Observation has nested in it (optionally, [0..1]) an Allergy Status Observation whose value attribute comes from 2.16.840.1.113883.3.88.12.80.68 (HITSPProblemStatus).  So, hopefully the answers above are directly applicable to Allergy Concerns/Observations as well.

Brian

----

Subject: RE: strucdoc digest: December 28, 2012
From: William Goossen Date: Sat, 29 Dec 2012 23:32:55 +0100

Brian,

The concern act would get a time for its creation. An observation of an onset would get its own time, which could be different from the concern, onset can be of earlier date. It is well explained in the care provision domain care structures topic. Unfortunately you will have to go back for the details to Sept 2009 dstu ballot

Vriendelijke groet,

William Goossen

---