FHIR Questionnaires and exchanging information

I had an interesting conversation on the skype ‘Implementers chat’ last week.

Like many others who are attending the FHIR connectathon in a couple of weeks, I’ve been working on scenarios involving  the Questionnaire resource (I’m writing a ‘template designer’ as well as a ‘form renderer’), and it occurred to me that it would be good to be able to share completed Questionnaires with others. I saw a similarity with sharing documents, and so asked the question whether the DocumentReference resource should be extended to permit the discovery and sharing on questionnaires as well.

Lloyd commented that his view was that the Questionnaire should not be a primary means of data exchange – that other resources are intended for that purpose, and that the Questionnaire doesn’t have ‘primacy’ over other resources. Grahame also commented that if you did wish to share a completed Questionnaire, then do so as you would any other resource.

That got me thinking.

A few years ago in New Zealand we developed a standard called the ‘Forms Server’ standard. The basic idea was that we would have a standardized way of representing a form template that could be shared between those needing to complete a form, and those needing the structured data within the completed form. A good example of this (and the one we were working with at the time) was a referral: in most cases when referring a patient to a specialist, there is data that is specific to that specialty that needs to be collected – a referral to a cardiologist will have different elements than one to a dermatologist.

We envisaged a central server that held these templates, and a standard that described their structure, plus the completion and transmission of the completed form. Potential referral recipients would upload templates containing the information they needed, and people making referrals would select the appropriate template to make the referral with. (We weren’t thinking of service discovery – just the templates and forms, and the manner that they could be shared). There was an associated standard way of getting data from referring systems (in our case primary care system), and another standard way of representing the actual referral, so in summary 3 major components:

  • Template structure and discovery (local standard)
  • Template pre-population (local standard)
  • Referral form and workflow (based on HL7 v2).

In the end, although the standards were implemented, it didn’t go the way we hoped. It was more of an implementation architecture than a standard, and because they were local to New Zealand, they were only ever implemented by one vendor (though the primary care vendors who were creating the referrals hosted the components and made a local pre-population service available), and so the only way of creating and updating templates was through that vendors system – as was the dissemination of the referrals.

We had achieved the goals of a particular project, but not in a way that encouraged other vendors to join the market, nor established any kind of re-use for other purposes.

So, fast forward to FHIR.

With the Questionnaire resource (and the Referral resource that is being worked on at the moment), there are now the pieces need to fulfil our vision in a truly standardized way. (In the following discussion, do remember that the Questionnaire resource fills the purpose of both template and completed form, using the status property to distinguish between them).

Template Structure and discovery is, of course, the Questionnaire resource and the standard FHIR query mechanisms. I think that there need to be a couple of extra fields to support discoverability – so you can categorize Questionnaire templates and search for specific ‘types’ of template. There are some proposals that we’ll discuss in Phoenix, but we can always use extensions if we need to.

Pre-population needs a couple of things. First the template needs a coded way of describing what information is needed, and the ‘filling’ system needs to be able to locate that data within it’s own data stores.

Well, each question in the Questionnaire has a ‘name’ property of type CodeableConcept, so all that’s needed for that is a standardized terminology like SNOMED, and possibly agreement between users about which codes to use – SNOMED is vast, and not that easy to navigate after all. So, a ValueSet containing the common terms (like usual medications, conditions, allergies etc.) to use might make sense.

In fact, the Questionnaire also allows us to use ValueSets to directly define the options for a question.

We might also want to describe the relationship between entries in a Questionnaire, and other FHIR resources or CDA documents to make it easier for implementers to convert between the two.

And the Referral resource is the final piece for this particular use case.

So we can imagine a workflow like this:

  1. The user locates the Questionnaire Template they wish to use
  2. The system downloads the Questionnaire and pre-populates it from the local data store based on the individual question.name entries.
  3. The user enters the remainder of the data described in the Questionnaire.
  4. When complete, the system constructs a Referral resource, and likely a number of other resources (like MedicationStatement, Observation, Condition) which are placed in a bundle and sent to the recipient using any of the described paradigms of exchange.

This workflow (and the implementing systems) is completely generic, and can be re-used in any other scenario where there is some standardized form of data collection and exchange – like routine assessments, progress notes, discharge summaries etc.

It’s important to appreciate that we’re using the Questionnaire as the interface between the user and the local system – not as the unit of exchange between systems, which would use resources specific to each purpose. In this case a Referral resource, but another example could be a Discharge Summary, which is a document. (I’ve glossed over some of the details of this exchange, which actually uses other resources like Order and OrderResponse, and of course there are security /privacy considerations as well.)

In fact, if we were half way clever we’d also re-use any appropriate FHIR server. For example, we’re currently looking at creating a ‘Record Locator Service’ (which could be a FHIR server hosting DocumentReference resources) – why not use the same infrastructure to store the Questionnaire templates?

So I’m starting to think that the Questionnaire could replace the List as my favourite FHIR resource.

Let’s see what happens in Phoenix…

 

 

 

 

The FHIR questionnaire: part 2

In this post we’re going to take a closer look at the internals of the Questionnaire.

The Questionnaire resource has 2 main parts:

  • The ‘header’ part that describes the Questionnaire
  • The contents – questions and answers

The Questionnaire has a dual personality. If it only has questions then it is a template (and the status has options of draft, published and retired). If it has answers, then it is a form instance (and the status has options of in progress, completed and amended). It could be argued that this difference should be made explicit with a specific property – for the mean time we’ll refer to these personalities as a template or an instance/form.

In the header is:

  • Status was discussed in the previous post. It actually serves a couple of purposes:
    • It identifies whether the Questionnaire is a template or an instance of a form
    • It indicates the workflow state
  • Authored. This is the date that the Questionnaire was authored – specifically the actual version of this resource – ie the date is updated whenever a new version is created.
  • Subject. Who the instance refers to.
  • Author. The person who recorded the information in the instance. When the instance has been completed by different people (eg the nurse fills in the start of an assessment form and the doctor completes the rest), then different versions of the instance will have different authors, and the version history will tell who entered what into the instance.
  • Source. The person who actually supplied the information (who may not be the same as the subject). For example, a mother may be supplying information about her child. If the subject is supplying the information then this property is not needed. Similarly to the author, this could conceivably be different across versions.
  • Name. This is used particularly for templates, and is the equivalent of the name of a form in the paper world – e.g. ‘Pre-operative assessment’. (The spec talks about a pre-defined list of questions – but it means the same). Interestingly, there is no concept of a ‘version’ of the form (as opposed to the usual FHIR resource versioning). For example, suppose the ‘Pre operative assessment template’ is modified. You have a couple of options:
    • Just update the template (new FHIR version). You do need to be careful about backwards compatibility  if form instances refer to external entities for rendering.
    • Change the status of the original to ‘retired’, and create a new one with the same name (and identifier). It may make sense to have an extension to explicitly state the template version.
  • Identifier.  Also used for templates, this allows a template to be part of a business workflow – e.g. the template has the identifier of “POA-2013/15 revA” – or some such. Potentially you could the identifier.period to specify the date range over which the template was valid – so when you create  or retire the template, you set the identifier.period.start and identifier.period.end properties appropriately.
  • Encounter.  This is an optional reference to the encounter where the form was completed.

The actual content of the Questionnaire is contained in an element named ‘group’. There can only be one top level group in a Questionnaire and it is optional (A Questionnaire with no questions would seem to be a particularly useless beast, but you might want to create the template, and then later add the questions I guess). As an aside – I suspect that a better name for ‘group’ here might have been ‘content’ – and for clarity that is how we’re going to refer to it here.

The content can be quite complex, being a hierarchy of sections (which are represented by groups), questions within the groups and groups within the questions…

Lets start from the bottom by thinking about the Questions.

Each Question has the following properties.

  • Name. A CodeableConcept that contains the code for each question. For example, suppose the question is ‘How many babies have you had (Parity)’, then the code could be the snomed code 118212000
  • Text. The text of the question as shown to the user in the form
  • Answer[x]. The answer to the question – if there is a single answer that is not drawn from a value set (we’ll discuss this in a moment). There is a fixed set of datatypes you can use here, and it isn’t possible in the Questionnaire to dictate what datatype to use – however you could create a profile for this purpose if you needed to. (A possible enhancement to Questionnaire would be to allow this in the Questionnaire as well). The permissible datatypes are: String, Decimal, Integer, Date, dateTime and instant. Obviously, the answer element will only be present in a completed form, not in a template.
  • Options. This allows a question to specify a set of possible answers – as you would use in a ‘picklist’ or ‘autocomplete’ control on a form. The options element refers to a ValueSet resource – which is a very sophisticated resource with many different ways to define the set of answers (I should do a post on this resource some time).
  • Choice. This is the selection that the user made from the defined options. It’s possible to make more than one choice from the list of options.
  • Data[x]. This allows you to refer to a specific resource, or include an answer that is of a datatype not included in the the Answer[x] element.
    • If you are including an answer of a specific datatype – maybe a CodeableConcept –  then the element name will include the datatype – in this case dataCodeableConcept.
    • If you are referring to a resource, then the element name is dataResource, and the contents are the usual resource reference (reference and display)
  • Remarks. Comments that the author of the form wishes to include about the answer – perhaps they feel the answer is incomplete or inaccurate. It should not be used for the answer itself.
  • Group. Allow you to have ‘questions within questions’. For example, the main question could be ‘Are you a smoker’, and the ‘sub-questions’ are only relevant (and possibly only shown) when the answer is ‘yes’.

If you haven’t seen the format ‘ Answer[x]’  or ‘Data[x]’ before (i.e. the [x] bit), then what that means is that the element name includes the datatype. For example, if you used a string as the answer, then the element name is answerString; an instant would be answerInstant, and so on.

As you can see, there are a number of different ways of specifying the possible answers to a question. In fact there are 3, and they are mutually exclusive (you can only have 1 of them):

  • Answer[x] – when there is a single, simple answer
  • Choice – when you select one or more options from a set of possible answers (including a full terminology – or subset of a terminology)
  • Data[x] – when there is a different datatype or a FHIR resource that is the answer. (And this could be constructed from other data entered in the form, or a selected from an existing resource).

A question arises: If you construct a resource based on data entered through a Questionnaire, how can you record both the original data and the resource in the Questionnaire? As of now, I’m not sure what the answer is – presumably you could create a Provenance resource that links the two, though that seems overly complex. Another possibility would be to use the remarks property. Or perhaps an extension on the answer that references the resource is the way to go. I need to think a bit more about the use cases where this would apply.

Here’s an example of a simple form. It’s a pregnancy assessment with 2 questions; one will be a simple text answer and the other is a selection from a pre-defined list. To specify the list, we’ve included a ValueSet as a contained resource and expanded the options to include the name of each option so that they can easily be displayed to the user. (go check out the ValueSet in the spec if these terms are unfamiliar). If this particular set of options was used by multiple Questionnaires then it might make sense to save it as a separate ValueSet resource and reference it from the question rather than containing it.


<Questionnaire xmlns="http://hl7.org/fhir">
     <text>
         <status value="additional"/>
         <div xmlns="http://www.w3.org/1999/xhtml">
             <p>An example of a Questionnaire being used as a template</p>
             <p>Could Place the template HTML Here</p>
         </div>
     </text>
     <contained>
         <ValueSet id="vs1">
             <name value="Parity Options"></name>
             <description value="The list of possible responses for Parity"/>
             <status value="active"/>
             <compose>
                 <include>
                     <system value="http://snomed.info/sct"/>
                     <code value="127364007"/>
                     <code value="127365008"/>
                 </include>
             </compose>
             <expansion>
                 <timestamp value="2014-02-27T12:30:10Z"/>
                 <contains>
                     <system value="http://snomed.info/sct"/>
                     <code value="127364007"/>
                     <display value="Primagravida (First Pregnancy) "/>
                 </contains>
                 <contains>
                     <system value="http://snomed.info/sct"/>
                     <code value="127365008"/>
                     <display value="Second Pregnancy"/>
                 </contains>
             </expansion>
         </ValueSet>
     </contained>
     <status value="published"/>
     <authored value="2014-02-27"/>
     <name>
         <coding>
             <system value="http://orionhealth.com/fhir/questionnaire#templatecodes"/>
             <code value="pregAss"/>
             <display value="Pregnancy Assessment"></display>
         </coding>
     </name>
     <group>
         <name>
             <coding>
                 <system value="http://orionhealth.com/fhir/questionnaire#sectioncodes"/>
                 <code value="subj"/>
                 <display value="Subjective entries - what the patient says"/>
             </coding>
         </name>
         <header value="Subjective"/>
         <text value="Use this section to record the patient history"/>
         <group>
             <question>
                 <name>
                     <coding>
                         <system value="http://snomed.info/sct"/>
                         <code value="127364007"/>
                         <display value="Primagravida (First Pregnancy) "/>
                     </coding>
                 </name>
                 <text value="How many Pregnancies"/>

                 <choice>
                     <code value="53881005"/>
                     <display value="None"/>
                 </choice>
                 <options>
                     <reference value="#vs1"/>
                 </options>

             </question>
             <question>
                 <name>
                     <coding>
                         <system value="http://snomed.info/sct"/>
                         <code value="118212000"/>
                     </coding>
                 </name>
                 <text value="What is the Parity (Number of live births)"/>
                 <answerInteger value="0"/>

             </question>
         </group>
     </group>
 </Questionnaire>

As I was writing this post, there were a number of areas where I wondered if the Questionnaire could be modified to improve its usability (of course, it may simply be that I don’t fully understand the intentions behind it’s use – it’s one of the more complex resources). These are:

  • It would be nice to be able to be explicit about the version of a template. Eg – that this is the second revision of an assessment form. (This is different to the FHIR resource versioning)
  • Should there be an indicator – or a list – when a single form has had multiple authors or sources.
  • Should there be some explicit way of marking a Questionnaire if it is a template, or is inferring this from the status still be best way to go.
  • Should the top level ‘group’ be better named as  ‘content’
  • Allow a question to define the expected answer format (must use a profile at the moment)
  • Does the term ‘section’ make more sense than ‘groups’

This nicely leads me back to the connectathon. One of the key purposes of the FHIR connectathon – and the reason for choosing a theme – is to support implementers as they actually use these resources, and to feed back issues that arise during this  into the resource design process. I think that the Questionnaire is going to be one of the more commonly used resources, so it’s a good time to look at it in detail.

You really should be there!

We aren’t quite done with Questionnaire yet – next time we’ll take a closer look at the grouping structure, and the standard extensions.

FHIR Questionnaire: Connectathon 6

The theme for the next FHIR Connectathon has just been decided by the FHIR Management Group, and this time round we’re going to explore the Questionnaire resource. The reason for choosing this is that there is interest in this resource from a number of significant organizations in the healthcare space, and because it supports one of the core requirements in healthcare – the ability to collect information using a form, and to extract information from that form to populate or update a medical record, while always keeping a ‘copy’ of the form.

It’s important to appreciate that the purpose of the Questionnaire is in the collection of information – not to act as a ‘repository’ of that data for later searching. In other words, if the Questionnaire collects something that needs to be recorded outside of that form – like a Condition – then the correct thing to do is to create a formal Condition resource and store that. Searching for data within the Questionnaire is certainly technically feasible, but is discouraged – the spec doesn’t even define any standard search parameters for this.

It is still possible to refer to a Resource from the Questionnaire  – you might want to do this if sending a completed Questionnaire to someone else  and wish to include the created resources in a bundle – but to do that you must have already extracted the data, created the resource, and then placed a reference to it within the Questionnaire. In some ways, this is like a FHIR Document – where the Questionnaire is analogous to the Composition resource – although the purpose is quite different. And, like a document, you can include all the resources in a bundle and sign it. (We talked about signing in the post on tamper proof auditing)

If you want to be able to record that the resource was created from data in a questionnaire, then the Provenance resource should be used. Provenance.target would refer to the resource, and Provenance.agent would refer to the Questionnaire.

At a high level, there are at 2 ways to use the Questionnaire:

  • As a ‘template’, containing only the questions – and potentially layout. (Template is a really overloaded term unfortunately).
  • As a ‘form instance’, containing the questions and the answers to those questions, or with the answers only (in which you would need to refer to something else to render it).

The Questionnaire.status property is used to distinguish a specific resource – the diagram below shows how this works.

questionnaire workflow

When it comes to using a Questionnaire to create a form, a common workflow might be:

    1. Select a blank Questionnaire from a set established as templates. These would be Questionnaire resources with a code of ‘published’.
    2. Prepopulate the Questionnaire from data sources if available. For example, you might want to include the current medication list or conditions.
    3. Render the Questionnaire as a form for the user to complete
    4. Save the completed Questionnaire as an interim Questionnaire.
    5. Complete the Questionnaire.
    6. Construct any other resources from the Questionnaire, and place a reference to them in the Questionnaire.
    7. Save the Questionnaire resource

To store a Questionnaire, you save the resource in the data store in the same way as any other resource. As described above, there may be other resources that were created on the basis of data entered in the Questionnaire that can be referred to from the Questionnaire.

To display a completed Questionnaire (form) to an end user, the simplest way is to store that rendition in the text property of the resource. In that way, any system with minimal FHIR compliance can retrieve and display it. This also gives the creator of the form control over the display format, which senders often require. Of course, as the resource contains structured data it can be rendered in a different way if required – e.g. on a mobile device. If storage space is an issue, then an alternative is to store the answers only in the Questionnaire – with a minimal text property – and require the consumer to retrieve a display template and render locally. The same applies to the a template: you could include the layout in the text element, or require that the recipient render it.

Well that’s an overview of the Questionnaire resource. In the next post we’ll dig a bit more into its structure, and go over this workflow in more detail.