Introduction

An HL7™ CDA™ document is encoded in Extensible Markup Language (XML) format. This is a computer-readable format rather than human-readable. The Generic Clinical Document Style Sheet takes a CDA document and transforms it from XML into HTML to enable a web browser to display it in a human-readable way.

Content

The Generic Clinical Document Style Sheet simplifies the development process by providing vendors with a sample implementation of a style sheet which will render all CDA documents defined by the Australian Digital Health Agency.

The Agency has published a CDA Rendering Specification2 specifying the features that are expected from a rendering system when displaying a CDA document. The style sheet follows this specification, implementing the requirements that are specific to “rendering systems”.

However, using only the style sheet will not be sufficient to meet all the conformance points of the specification.

The style sheet will render all Agency-defined CDA documents, taking specific (well-known) data from the CDA header and rendering it as per the CDA Rendering Specification. The CDA body will contain narrative text sections following the defined format of the CDA Rendering Specification, which allows the style sheet to render those sections using a generic set of rules.

As a prerequisite, the style sheet will assume the CDA document is well-formed and conforms to all specifications relevant for the type of clinical document. This particularly includes the conformity of the CDA document to the requirements of the CDA Rendering Specification that are related to “authoring systems”.

Additional Content - PDV

The PCEHR Prescription and Dispense View CDA Style Sheet (XSLT) (referred to as “PDV Style Sheet” in this product data sheet) takes a PCEHR Prescription and Dispense View CDA document and transforms it from XML into HTML to make it human readable through a browser. The PDV Style Sheet has a number of additional features which allow it to be more interactive than the “Generic Style Sheet”.

The PDV Style Sheet simplifies the development process by providing vendors with a sample implementation of a style sheet which will render the NEHTA-defined PCEHR Prescription and Dispense View CDA document.

In contrast to the Generic Style Sheet, the PDV Style Sheet has a number of parameterised configuration options, including turning javascript on. Javascript is used to allow expandable or contractible sections within the view to give a better user experience.

The other main difference from the Generic Style Sheet is that the PDV Style Sheet uses the atomic data from the CDA body of the document, as opposed to using the pre-defined narrative that the Generic Style Sheet uses. This is documented in the PCEHR Prescription and Dispense View Presentation Guide.

The presentation guide defines the features that are expected from a rendering system when displaying the PCEHR Prescription and Dispense View CDA document. The PDV Style Sheet follows this specification, implementing the requirements that are specific to the “view” portion of the guide. However, using only the PDV Style Sheet will not meet all the conformance points of the specification.

The PDV Style Sheet will assume the CDA document is well formed and follows the PCEHR Prescription and Dispense View CDA Implementation Guide.

Style Sheets

This is a software library that provides the Australian Digital Health Agency Generic CDA Stylesheet hereinafter referred to as the "Agency Stylesheet". The Agency Stylesheet is a reference implementation and may be used as a component of a CDA document Rendering System compliant to the Agency CDA Rendering Specification (CDA RS) in accordance to the requirements below. It remains your responsibility to test and validate the use of the "Agency Stylesheet" to make it production ready within a CDA document Rendering System.

Overview

The Agency Stylesheet is an XSLT 1.0 transform which transforms CDA documents conforming to Agency CDA Implementation Guides and the CDA Package Specification into an HTML 4.01 (CSS 2.1 and JavaScript 1.5) document which may then be displayed in a web browser.

The Agency Stylesheet together with a compliant Web Browser and an XSLT Stylesheet processor software constitutes a Rendering System compliant with the CDA RS.

In accordance with the CDA RS, the HTML document produced by the Agency Stylesheet displays both the Banner and the Details of the header. The Details of the header are separated into the following parts of the display:

• A General Document panel containing the Document Metadata, Patient, Facility, and Encounter Details along with an Organisational Logo.
• This panel is displayed near the top of the document under the fixed banner and users may click a button to hide and reveal this section.
• A Participants Panel which includes the details of the participants apart from the patient’s Nominated Primary Healthcare Providers
• A Primary Recipients Panel which includes the details of the primary information recipients contained in the CDA document.
• An Other Recipients panel which contains the details of any other (non-primary) recipient contained in the CDA document. This panel is displayed at the end of the document.
• A Nominated Primary Healthcare Providers panel which contains the details of the patient’s Nominated Primary Healthcare Provider participants contained in the CDA document. This panel is displayed above the Other Recipients Panel.

The Agency Stylesheet transforms the narrative blocks in the Structured Body of a CDA document into individual panels in the produced HTML document, in the same order in which they appeared in the original CDA Document.

The Structured Body Section title elements in which each Narrative Block is found will be included at the top of each of these panels and be clearly highlighted. These panels will be displayed between the Primary Recipients and Nominated Primary Healthcare Providers panels when the produced HTML document is viewed.

Operational Requirements

When using the Agency Stylesheet as part of a CDA RS compliant Rendering System, the following operational requirements apply:

• The Agency Stylesheet SHALL be executed using an XSLT 1.0 compatible processor.
• The input CDA Document SHALL be conformant with existing Agency CDA Implementation Guides and the CDA Rendering Specification.
• The output HTML document of the Agency Stylesheet SHALL be displayed using an HTML 4.01, JavaScript 1.5 and CSS 2.1 compatible rendering engine or software which employs such a rendering engine (e.g. a web browser).
• Rendering Systems SHALL ensure the display they intend to view the HTML document produced by the Agency Stylesheet has a resolution of at least 1024x768 pixels. Note that this does not exclude smaller screen sizes (e.g. smart phones and tablets) if they allow scrolling the display to view the entire document.
• Rendering Systems SHALL provide appropriate input devices to allow a user to scroll through the entire document contents and view any PDF, RTF or text attachments.
• The Agency Stylesheet execution does check the CDA Rendering Implementation Guide version if present in the CDA document. If a newer version of this guide is asserted in the CDA document, the Banner in the produced HTML document will alert the user and require input to display the rest of the document.
• The Agency Stylesheet presents the contents of the Banner as the document rendering view title as found in the title in the header of the produced HTML document.
• Rendering Systems SHALL check the versions prior to executing the Agency Stylesheet.
• Implementers are advised that current web browsers may allow users to define settings which might override HTML stylesheet elements. As this could potentially lead to clinically relevant information being rendered outside viewable screen space, it is suggested that appropriate measures are taken prevent this from occurring.
• Rendering Systems using the Agency Stylesheet SHALL NOT allow users to override the presentation and style contained in the HTML produced by the Agency Stylesheet.
• Rendering Systems using the Agency Stylesheet SHALL ensure that the title of the resulting HTML document produced is printed at the top of every page when printed.
• Rendering Systems using the Agency Stylesheet SHALL ensure that the “Page N of T” marker is printed at the bottom of every page when the HTML document is printed.
• Rendering Systems using the Agency Stylesheet SHALL ensure that background colours and images are printed when printing the output of the AgencyStylesheet.
• Rendering Systems using the Agency Stylesheet SHALL ensure that the view is shrunk to fit the page when printing the output of the Agency Stylesheet.
• The style sheet version can be displayed at the bottom of the document if the styleSheetVersionDisplay is set to true. If any modification is made to the style sheet, the version should be changed to reflect this and the variable VERSION_NOTE should be changed to indicate that the style sheet is now a "vendor" version as opposed to the "Agency" one. This should never default to true in a production environment.