Below you can find some important aspects of functional and non-functional requirements to IT systems, which we strive to meet in our work.
Currently, one of the main features of modern information systems, in particular, medical ones is interoperability. Interoperability is considered from two points of view:
- The first one is technical; it includes a format, syntax, and physical connectivity.
- The second is semantic, which involves the clear and consistent exchange of meaningful content.
It is important that both aspects are viewed simultaneously, like two sides of the same coin. It is essential to be able not only to send and/or accept data, but, what is more important, to understand them.
Moreover, ‘to understand’, first and foremost, refers to the readers of the information, i.e. to those people who use it, and only then to information systems. In other words, the ultimate objective of information systems’ interoperability is to establish mutual understanding between people engaged in common activities. In this context, we should regard interoperability as the mutual understanding of the content or similar understanding of the meaning. Below we list the requirements that ensure system interoperability.
Below we list the requirements that ensure system interoperability.
Functional Requirements
Functional requirements should be based on the approaches described in the HL7 Functional Model. The primary feature of any information system is its functionality. It defines the system’s purpose and field of application (medicine, business, mechanical engineering, etc.).
Interoperability of information systems cannot be ensured without the standardization of the functionality such systems support, including terminology, function bounds, content, semantic consistency, and completeness. One and the same application function used in various information systems and supporting similar activities shall be understood the same way and shall model a corresponding business function. The only differences are in the business function level and quality, ergonomics, scalability, usability, etc.
Moreover, functionality standardization is a relevant solution to classify information systems, which can guarantee adequate interaction between developers (solution providers) and users (customers).
Functional requirements for medical systems are specified in the HL7 Functional Model.
Methodological Requirements
To develop semantically interoperable information systems, it is necessary to use modern standards applied in medical informatics. This will return the result that corresponds to the modern level of IT development in medicine.
There are standards that define functional profiles, for example, the HL7 Functional Model. There are also terminology standards (LOINC, DICOM, SNOMED СT, ICD-10), data exchange standards (HL7, openEHR, IHE), standards of modelling medical knowledge and documents (openEHR and HL7 CDA), standards describing medical data storage structures (the openEHR Reference Model and HL7 RIM Reference Information Model), standards defining information systems architectures (openEHR, GOST R ISO/TS 18308-2008 Health informatics. Requirements for an electronic health record architecture).
Requirements for Modeling Tools
These requirements shall be based on the two-level modeling of clinical knowledge (openEHR Archetype Object Model), BPMN 2.0 (Business Process Model and Notation) and the Comsoft business modeling system.
Interface Requirements
Unlike the traditional approaches, which use a hierarchical menu to navigate the system, we build a data-driven navigation menu.
Integration Requirements
A computing platform shall consist of such integration components as a service bus, master data management system, document management, and a service-oriented architecture (SOA).
Access Requirements
‘Access’ means both the access to data and the access to system data processing functions. The role access complements the aforesaid options, i.e. it is a combination of the two described before. A role is a dynamic attribute, not static. After the access to data and data processing functions has been established, a user interface is generated. Therefore, every user of the system has his own interface.
Architecture Requirements
The analysis of best practices showed that the composite or component approach based on some platform technology is the best for the construction of modern informatisation systems.
We understand an instrumented runtime platform as follows:
- Tools and Mechanisms
- Unified interface environment (login, registration, and a top level navigation)
- Modeling tools
- Ready-to-use model engines
- Ready-to-use services implementing the support functions
- Tools to design and develop new nodes and components comprising the system
- Display form generators and report interpreters
- Viewers, navigators, query systems, and report generators
- Service customizers and configurators
- Master data and document management
- Service buses
- Other tools and mechanisms
- Repositories
- Reference models, functions, and services (standard nodes and components comprising the system)
- Metadata
- Knowledge bases
- Database schemas
- Documents
- Others
Imagine there is an informatisation system that needs to be developed for a certain company according to some specification. The platform approach allows to use an available instrumented runtime system which is configured and customized according to the requirements outlined in the specification.
The platform technology is a system that can be used to support activities performed by one or more companies in a traditional or cloud mode after it has been customized.