Arden syntax

Arden syntax is a markup language used for representing and sharing medical knowledge. This clinical and scientific knowledge language is used in an executable format by clinical decision support systems to generate alerts, interpretations, and to screen and manage messages to clinicians. This syntax is used to share medical knowledge within and across many health service institutions. Rule sets, called Medical Logic Modules, comprise enough logic to make a single medical decision. Medical logic modules are written in Arden syntax, and are called by a program - an event monitor - when the condition they are written to help with occurs. Arden syntax is a markup language used for representing and sharing medical knowledge. This clinical and scientific knowledge language is used in an executable format by clinical decision support systems to generate alerts, interpretations, and to screen and manage messages to clinicians. This syntax is used to share medical knowledge within and across many health service institutions. Rule sets, called Medical Logic Modules, comprise enough logic to make a single medical decision. Medical logic modules are written in Arden syntax, and are called by a program - an event monitor - when the condition they are written to help with occurs. Arden syntax was formerly a standard under ASTM, published in 1992, and is now part of Health Level Seven International. Arden syntax version 2.0 was published by HL7 in 1999. Arden syntax version 2.10 is the current version. The syntax offers potential users help deciding if the standard is appropriate for their purposes. It offers users and implementors knowledge of how parts of the standard were designed to be used. It also provides authors of other standards an insight that might be helpful in their own attempts in future designing of new languages. The name, 'Arden Syntax', was adopted from Arden House, located about 90 minutes north of Manhattan in Orange County, New York. Originally purchased by Edward Henry (E. H.) Harriman in 1885, the estate was given to Columbia University by his son W. Averell Harriman in 1950 following its use by the Navy in World War II. The house and grounds became a National Historic Landmark in 1966, and it is now a conference center. During the five-year IBM/CPMC R&D program, conferences and working sessions were hosted and led by CPMC at Arden House and attended by medical informaticians from several leading universities and hospitals, IBM personnel, and others directly or indirectly involved in the program. The 'Arden Syntax' name was chosen in recognition of important milestones achieved at Arden House in the development and refinement of the syntax and its implementation. The unit of representation in the Arden syntax is the Medical Logic Module (MLM). A Medical logic Module is composed of four categories, namely maintenance, library, knowledge and resources, with appropriate slots. Arden Syntax is an instance of a Knowledge Resource-Centric Knowledge Integration Architecture, where the knowledge resources command the delivery mechanisms of clinical decision support system. This category contains metadata about the MLM. The maintenance category consists of slots that indicate maintenance information unrelated to the medical knowledge in the module. The first slot is the title which gives a brief description of the module followed by a file name, a distinct identifier used to specify the MLM. The third slot is the version which specifies the version used. It also maintains a track of updates to the MLMs. A version slot is followed by institution and author slots that specify where the MLM is written and the person who wrote it. The sixth slot is the specialist slot that names the person in the institution liable for validating and installing the MLM in the institution. This slot is always meant to be blank when transferring information from one institution to another. This slot is followed by date and validation slots which show the date at which MLM was last updated. The validation level is set by the specialist, it indicates that the MLM is only used for testing. These slots are used for knowledge base maintenance and change control. This category contains five slots called purpose, explanation, keywords, citations and links. The purpose slot explains what a particular MLM is used for, whereas the explanation slot illustrates how an MLM works. Terms that can be used to search through a knowledge base of MLM is supplied by a keyword slot. The citation and link slots are optional. References to literature that support MLM's medical behaviour are included in the citation slot. Institution specific links to other sources of information such as electronic textbooks and educational modules are contained in the links slot. This category contains the actual medical knowledge of the MLM. It consists of type, data, priority, evoke, logic and action slots. The way in which MLM is used is known by type slot. Terms used in the rest of the MLM are defined by the data slot. Its goal is to separate those parts of the MLM that are specific to an institution from the more generic parts of the MLM. The order in which the MLM must be invoked are indicated by the priority, which can be a number from 1 (Last) to 99(first). It is a rarely used optional slot. An MLM can be activated by an event, or by a direct call from an MLM or an application programme which is specified by the evoke slot. A real medical condition or rule to test for is contained in the logic slot which may include compound calculations. The action slot creates a message that is sent to the health care provider, such as sending an alert to the destination, evoking other MLMs and returning values. The urgency slot is optional; it can be a number from 1 to 99 which indicates the importance of an MLMs action or message.