Introduction to this Implementation Guide
This Implementation Guide uses FHIR defined resources – Composition Resource, Questionnaire Resource, QuestionnaireResponse Resource, Patient Resource, Practitioner Resource, ServiceRequest Resource and Bundle from FHIR R4. For details on HL7 FHIR R4 see http://hl7.org/fhir/r4.
The Order & Referral by Form (ORF) Implementation Guide describes how forms for eReferrals, requests for information (such as diagnostic imaging results, lab results, discharge reports etc.) can be defined, deployed and used in order to achieve a syntactical and semantically consistent cross enterprise information exchange.
The Implementation Guide supports creation and domain wide deployment of forms for structured and coded information exchange as well as exchange of such forms for referral, orders etc. The Implementation Guide relies on FHIR e.g. the questionnaire resource. Because the Implementation Guide relies heavily on the FHIR Resources Questionnaire and QuestionnaireResponse, forms are addressed here as Questionnaires.
This Implementation Guide concerns directional information exchange between institutions such as requests for referral, requests for previous imaging results, requests for second opinions etc. as well as corresponding responses. Such request are often done – or could be done – by means of structured forms. The same may apply for responses or documents coming along in case the response consists of a particular payload (e.g. exam results). However, forms for these purposes are in general proprietary constructs and seldom suitable for further machine processing. Furthermore, such forms are more or less hard coded and concerned systems may not easily be updated for new use cases.
The ORF Implementation Guide addresses two issues:
Venders implementing the ORF Implementation Guide benefit of a high re-use potential. Applications which support the ORF Implementation Guide may be used for various settings of directional information exchange. The specific needs of a particular use case will be covered by a adequate design of the Questionnaire and the value sets being used.
When writing the ORF Implementation Guide, the authors had the following use case in mind: A human fills in a Questionnaire for a particular request and sends this Questionnaire to a receiver. There, a human reads the Questionnaire with its content. A corresponding response will work in the same way. There is possibly some payload coming with the Questionnaire: A request may be accompanied by results of preceding exams (e.g. images, reports); the response may be a diagnostic result.
The primary aim of the ORF Implementation Guide is to assure a consistent representation of Questionnaires at both – filler- and receiver – site. But there is the need for further machine processing: at filler site in terms of prepopulating attributes with content from other applications (e.g. demographic data of a patient) whereas the receiver may want to have the content of the form ready for further processing in his applications. Obviously the two aims – semantic interoperability and flexibility in the definition of Questionnaires – are contradictory. The ORF Implementation Guide addresses this problem by a mandatory set of mandatory given elements and codes with defined meaning which are part of every Questionnaire in the ORF Implementation Guide. It is up to a SDC Form Designer to create Questionnaires with additional use case specific elements.
Applications claiming for conformance with the ORF Implementation Guide shall:
Venders of applications with Questionnaire Filler/Questionnaire Receiver Actors are strongly recommended to implement interfaces to other applications (such as HIS and PACS) for all data in the mandatory given elements of Questionnaires.
Applications designed like this will provide out-of-the-box interconnectivity for mandatory given elements as well as out-of-the-box interoperability for all questionnaires as far it concerns user interfaces at filler and receiver site.
Nothing speaks against interfaces for data in the use case specific part of a particular Questionnaire. One has however to keep in mind, that such interfaces are tied to a specific questionnaire. Ownership or other means, which prevent changes of the questionnaire by third parties, are therefore advisable.
The ORF Implementation Guide deals with Transport, Workflow and Content. It is based on FHIR resources and in particular the FHIR Questionnaire resource. FHIR specifies RESTful Web services as a mean for transport. An implementation based on RESTful Web services is strongly recommended however not mandatory to comply with the ORF Implementation Guide. Workflow is addressed by the scope of ORF Implementation Guide which addresses directional information exchange with request and response. Content is defined by a set of mandatory mandatory given elements and codes and the possibility to extend both as required by the use cases addressed.
This Implementation Guide depends on the SDC Implementation Guide:
Questionnaires and forms permeate healthcare. They are used to capture administrative data, claims data, clinical information, research information, for public health reporting - every type of data that is manipulated by healthcare systems. They provide a user-friendly mechanism for capturing data in a consistent way. In FHIR, forms are represented using the Questionnaire resource and completed forms are represented using the QuestionnaireResponse resource. The base FHIR specification defines these resources but doesn't provide much guidance around how they should be used, nor does it set minimal expectations for interoperation. The SDC Implementation Guide provides a set of guidance around the use of Questionnaire and QuestionnaireResponse.
These sections define the different use-cases supported by SDC, specify the profile(s) needed to meet the use-cases.
To be considered SDC-conformant, a system must adhere to the requirements defined by at least one of these statements. Some systems might choose to comply with more than one.
The relationship between these roles and a summary of how they can interact is shown in [Figure 1].
[Figure 1] SDC Role operations
This section defines the actors, transactions, and/or content modules specific to this Implementation Guide.
|Questionnaire Filler||A system that renders Questionnaires and allows for filling in. The Questionnaire Filler is also responsible for filling in the corresponding resources in the Bundle, corresponds to the SDC Form Filler.|
|Questionnaire Receiver||A system that receives a Bundle (according to the Questionnaire) from a Questionnaire filler and renders it, corresponds to the SDC Form Receiver.|
[Table 1] Actors in the ORF Implementation Guide
[Figure 2] Questionnaire Handling Actor Diagram
[Figure 2] shows the actors directly involved in the ORF Implementation Guide and the relevant transactions between them. Actors which have a mandatory grouping are shown in conjoined boxes.
|Questionnaire Filler||Submit Bundle [CH:ORF-1]||O||3.1|
|Questionnaire Receiver||Submit Bundle[CH:ORF-1]||O||3.1|
[Table 2] Actors in the ORF Implementation Guide
[Table 2] lists the transactions for each actor directly involved in the Order & Referral by Form (ORF) Implementation Guide. To claim compliance with this Implementation Guide, an actor shall support all required transactions (labeled “R”) and may support the optional transactions (labeled “O”).
The Submit Bundle transaction is marked as optional to allow solutions which choose a different communication transaction method like IHE XDS, XDR, XMD to be conform with this Implementation Guide.
A product implementation using this Implementation Guide group actors from this with actors from a workflow or transport Implementation Guide to be functional. The grouping of the content module described in this Implementation Guide to specific actors is described in more detail in the “Required Actor Groupings” section below.
[Table 3] lists the content module defined in the Order & Referral by Form (ORF)) Implementation Guide. To claim support with this Implementation Guide, an actor shall support all required content modules (labeled “R”) and may support optional content modules (labeled “O”). The content module is based on the [Swiss core] profiles.
|Questionnaire Filler||ORF Content Module [Note 1]||R||Vol 3|
|Questionnaire Receiver||ORF Content Module [Note 1]||R [Note 1]||Vol 3|
[Table 3] Order & Referral by Form (ORF) Implementation Guide - Actors and Content Modules
[Note 1]The content of the form depends on the form which itself is defined by the FHIR Questionnaire The FHIR Questionnaire defines elements and structure of the form. Codes for coded attributes are provided with a corresponding value set (details see ORF Content Module)
Most requirements are documented in Transactions (Volume 2) and Content Modules (Volume 3). This section documents any additional requirements on Implementation Guide's actors.
Questionnaire Filler and Questionnaire Receiver Actors may be implemented on a mobile device, although this is not the primary setting in mind. All other Actors will rather be implemented in a stationary setting because the use case addressed involve mostly stationary applications.
Options that may be selected for each actor in this profile, if any, are listed in [Table 4]. Dependencies between options when applicable are specified in notes.
|Questionnaire Filler||No options defined||--|
|Questionnaire Receiver||No options defined||--|
[Table 4]ORF - Actors and Options
An Actor from this Implementation Guide (Column 1) shall implement all of the required transactions and/or content modules in this profile in addition to all of the transactions required for the grouped actor (Column 2).
If this is a content module, and actors from this Implementation Guide are grouped with actors from a workflow or transport profile, the Content Bindings reference column references any specifications for mapping data from the content module into data elements from the workflow or transport transactions.
In some cases, required groupings are defined as at least one of an enumerated set of possible actors; this is designated by merging column one into a single cell spanning multiple potential grouped actors. Notes are used to highlight this situation.
Section 1.5 describes some optional groupings that may be of interest for security considerations and section 1.6 describes some optional groupings in other related profiles.
|ORF Actor||Actor to be grouped with||Reference||Content Bindings Reference|
|Questionnaire Filler||Questionnaire Receiver||1.1||Volume 3|
|Questionnaire Receiver||Questionnaire Filler||1.1||Volume 3|
|Questionnaire Filler||CT Time Client||ITI TF-1: 7.1||na|
|Questionnaire Receiver||CT Time Client||ITI TF-1: 7.1||na|
[Table 5]ORF - Required Actor Groupings
Dr. Miller has a new Patient John Doe who has had an MRI at the radiology service “S-U-P-E-R-XR”. Dr. Miller retrieves a special order questionnaire from the SDC Form Manager at S-U-P-E-R-XR which allows ordering of images and reports of previous exams. Dr. Miller fills in this questionnaire and sends it back. At S-U-P-E-R-XR, a staff member will fill in another Questionnaire with a reply, attaches images and reports an sends all to Dr. Miller.
A resource server should not return any patient information unless proper authentication and communications security have been proven.
There are many reasonable methods of securing interoperability transactions. These security models can be layered in without modifying the characteristics of the ORF Profile transactions. The use of TLS is mandatory.
User authentication on mobile devices is encouraged using Internet User Authorization (IUA) Profile. The network communication security and user authentication are layered in at the HTTP transport layer and do not modify the interoperability characteristics defined in the ORF Profile.
The Security Audit logging (e.g., ATNA) is recommended. Support for ATNA-based audit logging on the mobile health device may be beyond the ability of this constrained environment.
In case vendors decide to include the Patient ID (patient.identifier) as a query parameter on the Resource URL (what would be out of the scope of ORF Implementation Guide), this URL pattern would present a risk when using typical web server audit logging of URL requests, and browser history. In both of these cases the URL with the patient identity would be clearly visible. These risks should be mitigated in system or operational design.
This section corresponds to Transaction CH:ORF-1. Transaction CH:ORF-1 is used by the Questionnaire Filler and Questionnaire Receiver. This is a combination of extracting resources outlined in the SDC Workflow 10.1 Optional EHR extracts information from Questionnaire Response and sending a Bundle including the extracted information according to Volume 3 and Questionnaire Response to the Questionnaire Receiver.
This transaction is used to submit a filled in questionnaire together with required additional resources and attachments in a Bundle from a Questionnaire Filler to a Questionnaire Receiver.
[Figure 3] Use Case Diagram
|Questionnaire Filler||A system that allows querying a SDC Form Manager in order to fill in the elements for a Questionnaire Response. Upon completion, a corresponding bundle will be submitted to the Questionnaire Receiver.|
|Questionnaire Receiver||A system that receives bundles and processes them compliant to the ORF Profile.|
[Table 6]Actor Roles
|HL7 FHIR||Fast Healthcare Interoperability Resources http://hl7.org/fhir/r4/index.html|
|HL7 SDC IG||Structured Data Capture Implementation Guide http://build.fhir.org/ig/HL7/sdc/index.html|
|IETF RFC 2616||Hypertext Transfer Protocol – HTTP/1.1|
|IETF RFC 7540||Hypertext Transfer Protocol – HTTP/2|
|IETF RFC 3986||Uniform Resource Identifier (URI): Generic Syntax|
|IETF RFC 6585||Additional HTTP Status Codes|
|IHE Appendix on HL7 FHIR||https://www.ihe.net/uploadedFiles/Documents/ITI/IHE_ITI_Suppl_Appx-Z.pdf|
[Figure 4] Interaction Diagram
The transaction uses the HTTP POST method on the target Questionnaire Receiver endpoint to convey the questionnaire bundle as a FHIR transaction.
After the Questionnaire is completed by the Questionnaire filler user, the Questionnaire Filler submits a the corresponding bundle to the Questionnaire receiver.
The Questionnaire Filler shall initiate a FHIR “transaction” using a “create” action by sending an HTTP POST request method composed of a FHIR Bundle Resource containing the Composition resource and all resources referenced in, in particular one Questionnaire Resource, one QuestionnaireResponse Resource and additional resources according to the Questionnaire Profile.
The media type of the HTTP body shall be either
Submit Bundle is sent to the base URI as defined in FHIR. See http://hl7.org/fhir/r4/http.html for the definition of “http” access methods and “base”.
For complete information on constructing a FHIR Bundle Resource, see: http://hl7.org/fhir/r4/bundle.html
Bundle.meta.profile shall include the value
The Questionnaire Receiver shall accept both media types
On receipt of the submission, the Questionnaire Receiver shall validate the resources and respond with one of the HTTP codes defined in Section 126.96.36.199.2 Message Semantics.
The Questionnaire receiver returns a HTTP Status code appropriate to the processing, conforming to the transaction specification requirements as specified in http://hl7.org/fhir/r4/http.html#transaction
This message shall be sent once the questionnaire bundle is received and completely processed.
When the Questionnaire Receiver has successfully processed the POST transaction, then the Questionnaire Receiver shall return an HTTP response with an overall status code.
In order to allow the Questionnaire Filler to know the outcomes of processing the transaction, and the identities assigned to the resources by the Questionnaire Receiver, the Questionnaire Receiver shall return a Bundle, with type set to transaction-response, that contains one entry for each entry in the request, in the same order, with the outcome of processing the entry. See FHIR http://hl7.org/fhir/r4/bundle.html#transaction-response
Each entry element shall contain a response element which details the outcome of processing the entry - the HTTP status code. All other elements are not required.
On success, the Questionnaire Receiver shall return the HTTP status code 200 – OK.
Guidance on handling Access Denied related to use of 403 and 404 can be found in IHE Appendix on HL7 FHIR Z.7.
On failure, the Questionnaire Receiver shall return the HTTP status codes as follows:
In addition, the Questionnaire Receiver may also send 5xx HTTP status codes to indicate non-transaction related failures. Note that the Questionnaire Filler may also encounter non-FHIR endpoints which will not return an Bundle in the response.
The Questionnaire Receiver may return HTTP redirect responses (responses with HTTP status codes 301, 302, 303 or 307) in response to a request.
If the Questionnaire Receiver returns an HTTP redirect response (HTTP status codes 301, 302, 303, or 307), the Questionnaire Filler shall follow that redirection, although it may stop processing if it detects a loop.
The Questionnaire Receiver processes the results according to application-defined rules.
If a Questionnaire Receiver cannot automatically recover from an error condition, at a minimum, it should display the error to the user.
Questionnaire Receiver implementing this transaction should provide a Conformance Resource as described in IHE Appendix on HL7 FHIR Z.3 indicating the operation has been implemented.
This section describes the content of a form. The following definitions apply:
Request and responses consist of filled in questionnaires. Some elements of the questionnaire are mandatory given elements (such as author, data entry person, receiver etc. are always present in a questionnaire compliant to the ORF Implementation Guide. In addition, a questionnaire will contain elements which are use case specific. The ORF Implementation Guide makes no assumptions about the nature of such elements: structure and content (including coding of codes elements) are in the responsibility of those creating a form for a particular use case.
As this Implementation Guide is based on FHIR, the following rules apply:
Items, grouping of items, order of groups and order of elements within groups of a questionnaire shall be defined in a Questionnaire Resource. The Questionnaire Resource is defined by means of the SDC From Designer and made available by the SDC Form Manager.
Based on the Questionnaire, a Questionnaire Filler defines a QuestionnaireResponse and appropriate additional resources aimed at transmitting the information provided by the Questionnaire filler in a standardized structured form. Upon completion of the questionnaire, the Questionnaire Filler shall create a bundle with all resources mentioned above.
Questionnaires may be accompanied by additional material which can be attached or sent by postal mail (e.g. xray-films or paper documents). The use case may require some references between attached objects (e. g. which pdf-reports belongs to which imaging study).
A questionnaire shall have a set of mandatory given elements (e.g. author, data entry person, receiver etc. [Table 7] lists the mandatory given elements
|Name||Role taker||HL 7 V3R
|Author||X||X||Author||Practitioner||The person responsible for Form Content|
|Date Entry Person||X||X||DataEnterer||Practitioner||The person who has typed/filled in the Form Content.|
|Urgent Notification Contact for this document||X||X||PrimaryInformationRecipient||Practitioner||An information recipient to notify for urgent matters (e.g. in a radiology service, the Radiologist has to be called by phone right away at the time the images arrive.|
|Urgent Notification Contact for the Response to this document||X||X||PrimaryInformationRecipient||Practitioner||
An information recipient to notify for urgent matters about the response. (e.g. in a clinical setting, the referring doctor has to be called by phone right away at the time the images and reports arrive.
The Urgent Notification Contact for the Response can be specified already in the request. At the time the response is written, this element shall be populated to the Urgent Notification Contact element in the response
|Receiver||X||X||Practitioner||Person and/or institution who receives the Bundle|
|Patient||X||Patient||The principle target of a particular Form Content is one patient (for obstetrical and neonatal use cases see….).|
|PrecedentDocumentId||na||na||This element provides a link to the preceding document in a thread (e.g. from a response to the request|
|Date||na||na||Date, the document was created|
|Priority||na||na||DiagnosticOrderPriority||The priority shall be indicated in the one of the resources in the table “Optional given elements of a questionnaire”|
[Table 7] Mandatory given elements in Questionnaires compliant to the ORF Implementation Guide
There may be the need to provide a linkage between a particular files or between a particular file and an imaging study (e.g. a link between a PDF-File containing a report and a DICOM study). Such links shall be expressed with a DocumentReference as follows:
|type||(e.g. LOINC 18748-4 for Diagnostic Imaging Study)|
|data||Data inline, base64ed (contains the file; e.g. a PDF-Report)|
|Reference (ImagingStudy)||ImagingStudyResource provides StudyInstanceUID etc.|
FHIR depicts forms (questionnaires) in a Questionnaire Resource. A Questionnaire Resource can be conceived as an empty questionnaire where as the filled in questionnaire refers to the QuestionnaireResponse Resource. QuestionnaireResponse Resources are certainly structured but due to their flexibility in design not in a standardized manner. FHIR addresses this issue by means of its standardized resources.
The Order & Referral by Form Implementation Guide is based on two FHIR Resources profiles. For details on profiling FHIR see HL7 FHIR http://www.hl7.org/fhir/profiling.html. For details on FHIR resources and data-types see HL7 FHIR http://hl7.org/fhir/.
This section lists FHIR resources where this profile provides additional information. Resources not listed here follow the specifications of FHIR. For details refer to https://www.hl7.org/fhir/resourcelist.html.
|FHIR Composition Resource||FHIR Type||ORF Constraint||Notes|
|text||1..1||R||Narrative Text of the composition.|
|extension||ORFPrecedentDocument||Identifier||Identifier of the document which precedes this document in a thread.|
|identifier||Identifier||1..1||R||Identifier for this composition.|
|date||dateTime||1..1||R||Composition editing time|
|section||QA section must at least one of text, entries, or sub-sections.|
Additionally structured entries like ServiceRequest
The intention of the ORF Implementation Guide is to provide a standardized representation of forms at sender and receiver site as well. This is achieved with the Questionnaire Resource, which defines representation of all elements for the user (with the help of a CSS) and user interaction as well (e.g. with drop down lists).
This approach requires two things:
Both is achieved by assigning meaningful concepts to all elements concerned. For codes refer to Appendix A.
|FHIR Type||ORF Constraint||Notes|
|item||0..*||R||Questions and sections within the Questionnaire|
|linkId||string||1..1||R||Unique id for item in questionnaire|
||repeats||boolean||0..1||O||Whether the question can have multiple answers|
||answerValueSet||canonical(ValueSet)||0..1||(R)||Valueset containing permitted answers|
|item||0..*||Nested questionnaire items|
[Table8]Content of the Questionnaire resource
The QuestionnaireResponse Resource depends of the definition of the Questionnaire Resource and is therefore use case specific. For deriving QuestionnaireResponse Resources from the Questionnaire Resources refer to https://www.hl7.org/fhir/r4/questionnaireresponse.html.