Dynamic views of clinical statements - a short contribution to the debate

HL7 WGM – Clinical Statement Project 2006-01-12 David Markwell

Three distinct dynamic viewsand the motivations behind them

• Request & Report– To request a service– To report the results of a service either to a requester or to

another interested party• Document

– To maintain and exchange attestable information• Shared longitudinal record

– To make available an information resource that can be used for effective selective retrieval to support clinical decision support and aggregation for research, epidemiology and audit

• … there is overlap between these views– A report can be a document– A report or document can form part of a longitudinal record

• … but there are also differences– Authoring and ownership– Modification and status tracking

Three distinct dynamic views

1. Request & report• The request is “owned” by the requester/placer

– It can be sent to a filler or copy destination• The report is “owned” by the reporter/filler

– It can be sent to a placer or another destination to fulfil a request• The request and report are discrete information artefacts• The “owner” of an information artefact declares and controls

– the scope of completeness of the contained information– the status of the artefact and all its subcomponents

• A state changes in an “owned” artefact results in a “trigger event”– depending on business rules this may result in communication of that

artefact to other parties (recipients)• Receipt of a communication

– creates a representation of a new artefact in the recipient system; or – changes the state of a previously communicated artefact

Request & Report

Placer

Filler

Request

Updated report

Report

Supersedes

Fulfils

Three distinct dynamic views

2. Document• The document is “owned” by its author

– It can be stored and then accessed by other parties– It can be communicated and copied to other location where it may also

be accessed• Each document is a discrete information artefact• The “owner” of a document declares and controls

– the scope of completeness of the contained information– the status of the artefact and all its subcomponents

• Changes to a document effectively create a new document version– Itemized changes to a document may be explicitly tracked by reference – Whether or not this is done the new and old version of a document

exists in its their own right and might be referenced or viewed– Business rules may lead to notification of parties when a document of

interest to them is revised or updated• Receipt of a communicated document

– creates a representation of the document in the recipient system– may supersede an earlier version of an existing document

Document

Author / reader

Supersedes

Author / reader

Author / re

ader

Three distinct dynamic views

3. Shared longitudinal record• The record is “shared” by those who contribute to it

– Individual contributions are “owned” the relevant author• A shared record may exist in various forms

– Distributed• Parts of the record are held in different local application repositories –

typically in there original form– Centralised in a common repository

• Whether the record is distributed or centralized sharing may be– Real-time

• retrieved and communicated from its original store when needed– Cached

• a local image of the record in its original form– Locally stored

• a local copy of all or part of the record• Communications from the original store transformed to the form prescribed

by a local application

Three distinct dynamic views

3. Shared longitudinal record (continued)

• A shared record contains multiple discrete information artefacts – these may have different level of granularity – these have different original “owners”

• Users may need to correct or update fragments of the record – including statement made by others

• Changes and additions need to be communicated to other record sharers in ways that– correctly represent the provenance of changes and additions– refer updated or corrected fragments in a non-ambiguous manner

• Receipt of a communication requires– recognition of validity / originality / current etc of contained information

items– appropriate merging and updating of local held views of the record

• The objective a record that– is accurate, current, human-readable and processable– contains minimum of duplications or contradictions

R2 R3

Shared record

R1

asserts relationship

updatesdeletes

R2 R3

Shared record

R1

R4 ?

“Shared record” dynamic viewa few interesting issues

• Ability to reference previous statements pre/post change– Identifier scope

• Status and state changes– If status can only be changed by the author then another mechanism is

needed for updates and corrections• If one statement changes how does this affect

– Subsidiary statements (sub components of a statement)– Containing statements– Other related statements (i.e. cause and effect)– Condition nodes

• Record scaling and duplication– Sender may not know what the recipient record already contains– If everything is resent result is large messages– If everything received is tracked as part of record the record grows– Vicious circle of record size growth

• Impact of overlapping views– A shared record system will probably send requests and receive reports– A shared record will contain documents– Documents may be used to present summaries of a shared record