ASTM E1460-92

Specification for Defining and Sharing Modular Health Knowledge Bases Arden Syntax for Medical Logic Modules (Withdrawn 1999)

SCOPE
1.1 This specification covers the sharing of computerized health knowledge bases among personnel, information systems, and institutions. The scope has been limited to those knowledge bases that can be represented as a set of discrete modules. Each module, referred to as a Medical Logic Module (MLM), contains sufficient knowledge to make a single decision. Contraindication alerts, management suggestions, data interpretations, treatment protocols, and diagnosis scores are examples of the health knowledge that can be represented using MLMs. Each MLM also contains management information to help maintain a knowledge base of MLMs and links to other sources of knowledge. Health personnel can create MLMs directly using this format, and the resulting MLMs can be used directly by an information system that conforms to this specification.
1.2 The major topics are found in the following sections.

General Information

• Status: Withdrawn
• Publication Date: 31-Dec-1991
• Withdrawal Date: 09-Aug-1999
• ICS: 35.240.80 - IT applications in health care technology
• Technical Committee: E31 - Healthcare Informatics
• Drafting Committee: E31.90 - Executive

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Please contact ASTM International (www.astm.org) for the latest information.
An American National Standard
Designation: E 1460 – 92
Standard Specification for
Defining and Sharing Modular Health Knowledge Bases
(Arden Syntax for Medical Logic Modules)
This standard is issued under the fixed designation E 1460; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
Library Category 6.3
Purpose 6.3.1
1.1 This specification covers the sharing of computerized
Explanation 6.3.2
health knowledge bases among personnel, information sys- Keywords 6.3.3
Citations 6.3.4
tems, and institutions. The scope has been limited to those
Links 6.3.5
knowledge bases that can be represented as a set of discrete
Knowledge Category 6.4
modules. Each module, referred to as a Medical Logic Module
Type 6.4.1
Data 6.4.2
(MLM), contains sufficient knowledge to make a single deci-
Priority 6.4.3
sion. Contraindication alerts, management suggestions, data
Evoke 6.4.4
interpretations, treatment protocols, and diagnosis scores are Logic 6.4.5
Action 6.4.6
examples of the health knowledge that can be represented
Urgency 6.4.7
using MLMs. Each MLM also contains management informa-
Structured Slot Syntax 7
tion to help maintain a knowledge base of MLMs and links to Tokens 7.1
Reserved Words 7.1.1
other sources of knowledge. Health personnel can create
Identifiers 7.1.2
MLMs directly using this format, and the resulting MLMs can
Special Symbols 7.1.3
be used directly by an information system that conforms to this Number Constants 7.1.4
Time Constants 7.1.5
specification.
String Constants 7.1.6
1.2 The major topics are found in the following sections.
Team Constants 7.1.7
Mapping Clauses 7.1.8
Section
Comments 7.1.9
White Space 7.1.10
MLM Format 5
Organization 7.2
File Format 5.1
Statements 7.2.1
Character Set 5.2
Expressions 7.2.2
Line Break 5.3
Variables 7.2.3
White Space 5.4
Data Types 8
General Layout 5.5
Null 8.2
Categories 5.6
Boolean 8.3
Slots 5.7
Number 8.4
Slot Body Types 5.8
Time 8.5
Textual Slots 5.8.1
Duration 8.6
Textual List Slots 5.8.2
String 8.7
Coded Slots 5.8.3
Term 8.8
Structured Slots 5.8.4
List 8.9
MLM Termination 5.9
Query Results 8.10
Case Insensitivity 5.10
Operator Descriptions 9
Slot Descriptions 6
General Properties 9.1
Maintenance Category 6.2
Number of Arguments 9.1.1
Title 6.2.1
Data Type Constraints 9.1.2
Filename 6.2.2
List Handling 9.1.3
Version 6.2.3
Primary Time Handling 9.1.4
Institution 6.2.4
Operator Precedence 9.1.5
Author 6.2.5
Associativity 9.1.6
Specialist 6.2.6
Parentheses 9.1.7
Date 6.2.7
List Operators 9.2
Validation 6.2.8
Where Operator 9.3
Logical Operators 9.4
Simple Comparison Operators 9.5
Is Comparison Operators 9.6
This specification is under the jurisdiction of ASTM Committee E-31 on
Occur Comparison Operators 9.7
Healthcare Informatics and is the direct responsibility of Subcommittee E31.15 on
String Operator 9.8
Medical Knowledge Representation.
Arithmetic Operators 9.9
Current edition approved Feb. 15, 1992. Published April 1992.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Please contact ASTM International (www.astm.org) for the latest information.
E1460–92
3.1.1 Medical Logic Module (MLM), , n—an independent
Temporal Operators 9.10
Duration Operators 9.11
unit in a health knowledge base. Each MLM contains mainte-
Aggregation Operators 9.12
nance information, links to other sources of knowledge, and
Query Aggregation Operators 9.13
enough logic to make a single health decision.
Transformation Operators 9.14
Query Transformation Operator 9.15
3.2 Definitions of Terms Specific to This Standard:
Numeric Function Operators 9.16
3.2.1 time, , n—a point in absolute time. Also known as a
Time Function Operator 9.17
timestamp, it includes both a date and a time-of-day.
Logic Slot 10
Purpose 10.1
3.2.2 time-of-day, , n—hours, minutes, seconds, and possi-
Logic Slot Statements 10.2
bly, fractions of seconds past midnight.
Assignment Statement 10.2.1
If-then Statement 10.2.2 3.2.3 date, , n—Gregorian year, month, and day.
Conclude Statement 10.2.3
3.2.4 duration, , n—a period of time (for example, 3 days)
Call Statement 10.2.4
that has no particular start or end point.
Logic Slot Usage 10.3
Data Slot 11 3.2.5 institution, , n—a health facility of any size that will
Purpose 11.1
provide automated decision support or quality assurance.
Data Slot Statements 11.2
Read Statement 11.2.1
Event Statement 11.2.2 4. Significance and Use
MLM Statement 11.2.3
4.1 Decisionsupportsystemshavebeenusedforhealthcare
Argument Statement 11.2.4
Message Statement 11.2.5
successfully for many years, and several institutions have
Destination Statement 11.2.6
already assembled large knowledge bases. There are many
Assignment Statement 11.2.7
conceptual similarities among these knowledge bases. Unfor-
If-then Statement 11.2.8
Call Statement 11.2.9
tunately, the syntax of each knowledge base is different. Since
Data Slot Usage 11.3
nooneinstitutionwilleverdefineacompletehealthknowledge
Action Slot 12
base, it will be necessary to share knowledge bases among
Purpose 12.1
Action Slot Statements 12.2 institutions.
Write Statement 12.2.1
4.2 Many obstacles to sharing have been identified: dispar-
Return Statement 12.2.2
ate vocabularies, maintenance issues, regional differences,
If-then Statement 12.2.3
Call Statement 12.2.4
liability, royalties, syntactic differences, etc. This standard
Action Slot Usage 12.3
addresses one obstacle by defining a syntax for creating and
Evoke Slot 13
sharing knowledge bases. In addition, the syntax facilitates
Purpose 13.1
Events 13.2
addressing other obstacles by providing specific fields to enter
Evoke Slot Statements 13.3
maintenance information, assignment of clinical responsibility,
Simple Trigger Statement 13.3.1
links to the literature, and mappings between local vocabulary
Where Trigger Statement 13.3.2
Delayed Trigger Statement 13.3.3
terms and terms in the knowledge base.
Periodic Trigger Statement 13.3.4
4.3 The range of health knowledge bases is large. This
Evoke Slot Usage 13.4
specification focuses on those knowledge bases that can be
represented as a set of Medical Logic Modules (MLMs). Each
2. Referenced Documents
MLM contains maintenance information, links to other sources
2.1 ASTM Standards:
of knowledge, and enough logic to make a single health
E 1238 Specification for Transferring Clinical Laboratory
2 decision. Knowledge bases that are composed of independent
Data Messages Between Independent Computer Systems
rules, formulae, or protocols are most amenable to being
E 1384 Guide for Content and Structure of the Computer-
represented using MLMs.
Based Patient Record
4.4 This specification, which is an outcome of the
2.2 ISO Standards:
Columbia-Presbyterian Medical Center 1989 Arden Home-
ISO 8601 – 1988 Data Elements and Interchange
stead retreat on sharing health knowledge bases, is derived
Formats—Information Interchange (representation of
largely from HELP of LBF Hospital, Salt Lake City, UT (1) ,
dates and times)
and CARE, the language of the Regenstrief Medical Record
2.3 ANSI Standards:
System of the Regenstrief Institute for Health Care, Indianapo-
ANSI X3.4 – 1986 Coded Character Sets—American Na-
lis, IN (2).
tional Standard Code for Information Interchange (7-bit
ASCII)
5. MLM Format
3. Terminology
5.1 File Format—An MLM is a stream of text stored in an
ASCII file (ANSI X3.4 – 1986). One or more MLMs may be
3.1 Definitions:
placed in the same file. Within a file, an MLM begins with the
marker maintenance: and ends with the marker end:.
Annual Book of ASTM Standards, Vol 14.01.
Available from ISO, 1 Rue de Varembe, Case Postale 56, CH 1211, Geneve,
Switzerland.
4 5
Available from American National Standards Institute, 11 W. 42nd St., 13th The boldface numbers in parentheses refer to the list of references at the end of
Floor, New York, NY 10036. this standard.
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Please contact ASTM International (www.astm.org) for the latest information.
E1460–92
5.2 Character Set—Within an MLM only the printable 5.8.3 Coded Slots—Coded slots contain a simple coded
ASCII characters (ASCII 33 through and including 126), space entrylikeanumber,adate,oratermfromapredefinedlist.For
(ASCII 32), carriage return (ASCII 13), line feed (ASCII 10), example, the priority slot can only contain a number, and the
and horizontal tab (ASCII 9) may be used. The use of validation slot can contain only the terms production, re-
horizontal tab is discouraged because there is no agreement on search, etc.
how many spaces it represents. Other characters, like the bell 5.8.4 Structured Slots—Structured slots contain syntacti-
and backspace, are not allowed within the MLM. (There is no cally defined slot bodies. They are more complex than coded
limitation on the characters that may occur between MLMs slots, and are further defined in Section 7. An example of this
within a file; for example, a form feed character may separate kind of slot is the logic slot.
two MLMs even though it cannot occur within an MLM.) 5.9 MLM Termination—The end of the MLM is marked by
the word end followed immediately by a colon (that is, end:).
5.3 Line Break—Lines are delimited by line breaks, which
are any one of the following: a single carriage return, a single 5.10 Case Insensitivity—Category names, slot names, and
the end terminator may be typed in uppercase (for example,
line feed, or a carriage return-line feed pair.
END), lowercase (for example, end), or mixed case (for
5.4 White Space—The space, carriage return, line feed, and
example, eNd).
horizontal tab are collectively referred to as white space.
5.5 General Layout—Annex A1 contains a complete de-
6. Slot Descriptions
scription of MLMs expressed in BACKUS-NAUR Form. See
6.1 For each slot description, next to the slot name is an
Appendix X1 for MLM examples. (Planned editions and
indication of whether the slot is textual, textual list, coded, or
changes for future versions of this specification are listed in
structured, and whether it is required or optional. Slots must
Appendix X2.) A typical MLM is arranged like this.
appear in this order.
maintenance:
6.2 Maintenance Category—The maintenance category
slotname: slot-body;;
contains the slots that specify information unrelated to the
slotname: slot-body;;
health knowledge in the MLM. These slots are used for MLM
...
knowledge base maintenance and change control.
library:
6.2.1 Title (textual, required)—The title serves as a com-
slotname: slot-body;;
ment that describes briefly what the MLM does. For example,
...
title: Hepatitis B Surface Antigen in Pregnant Women;;
knowledge:
6.2.2 Filename (coded, required)—The MLM filename
slotname: slot-body;;
uniquely identifies an MLM within a single authoring institu-
...
tion. It is represented as a string of characters beginning with
end:
a letter and followed by letters, digits, and underscores (_). A
5.6 Categories—An MLM is composed of slots grouped
filename may be 1 to 80 characters in length. Filenames are
into three categories: maintenance, library, and knowledge. A
insensitive to case. The MLM filename is distinct from the
categoryisindicatedbyacategorynamefollowedimmediately
name of the ASCII file which happens to hold one or more
by a colon (that is, maintenance:, library:, and knowledge:).
MLMs. For example,
Category names need not be placed at the beginning of a line.
filename: hepatitis_B_in_pregnancy;;
5.7 Slots—Within each category is a set of slots.
6.2.3 Version (coded, required)—The current version of the
5.7.1 Each slot consists of a slot name, followed immedi-
MLM is expressed as a fixed point number with two decimal
ately by a colon (for example,title:), then followed by the slot
places to the right of the decimal point. MLMs start at 1.00 and
body, and terminated with two adjacent semicolons (;;) which
advance by .01 for small revisions and by 1 for large revisions.
isreferredtoasdoublesemicolon.Thecontentoftheslotbody
For example,
depends upon the slot, but it must not contain a double
version: 1.00;;
semicolon.
6.2.4 Institution (textual, required)—The institution slot
5.7.2 Each slot must be unique in the MLM, and categories
contains the name of the authoring institution. For example,
and slots must follow the order in which they are listed in this
institution: Columbia University;;
standard. Some slots are required and others are optional.
6.2.5 Author (textual list, required):
5.8 Slot Body Types—These are the basic types of slot
6.2.5.1 The author slot contains a list of the authors of the
bodies:
MLM, delimited by semicolons. The following format should
5.8.1 Textual Slots—The textual slots contain arbitrary text
be used: first name, middle name or initial, last name, comma,
(except for double semicolon, which ends the slot). As the
suffixes, and degrees.
MLM standard is augmented, slots that are currently consid-
6.2.5.2 An electronic mail address enclosed in parentheses
ered to be textual may become coded or structured. An
may optionally follow each author’s name. Internet addresses
example of a textual slot is the title slot, which can contain
are assumed. Bitnet addresses should end in.bitnet and UUCP
arbitrary text.
addresses should end in .uucp. For example,
5.8.2 Textual List Slots—Some slots contain textual lists. author: John M. Smith, Jr., M.D. ([e-mail]);;
These are lists of arbitrary textual phrases separated by single 6.2.6 Specialist (textual, required)—The domain specialist
semicolons(;).Anexampleofatextuallistslotisthekeywords is the person in the institution responsible for validating and
slot. installing the MLM. This slot should always be present but
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Please contact ASTM International (www.astm.org) for the latest information.
E1460–92
blank when transferring MLMs from one institution to another. cardial infarction in emergency department patients with
It is the borrowing institution’s responsibility to fill this slot chest pain. N Engl J Med 1988;318(13):797–803.
and accept responsibility for the use of the MLM. The format ;;
is the same as for the author slot. 6.3.5 Links (textual, optional)—The links slot allows an
6.2.7 Date (coded, required)—The date of last revision of institution
...