Introduction This schema defines the DICOM constraint document. A DICOM constraint document defines rules to check the conformance of a DICOM content with respect to the DICOM standard and other organization-wide guidelines. This XML schema document defines the XML schema constraining constraint documents. A constraint document defines one or more constraint rules. A constraint rule is the unit of invocation for conformance checking. At run time, a user may invoke a PL/SQL or Java function to check the conformance of a DICOM content with respect to a particular rule. Each invocable rule is defined as a GLOBAL_RULE, which can reference other global rules internally. A constraint rule can be decomposed into individual predicates. A predicate can be a logical statement, a relational statement comparing values, a function call evaluation that returns a Boolean type, or a reference to other predicate definitions. Predicate definitions are recursive. A predicate can be a logical statement, which includes the logical OR of two other predicates. Each predicate can be a relational predicate. For example: (patientName=="Joe Smith" AND patientSex=="M") After being translated into a predicate, the preceding example becomes: An example to find an object that has (patientName="Joe Smith" AND patientSex=="M") 00100010 Smith Joe 00100040 M Constraint macros can be used to simplify the definition of complex constraint rules. Constraint macros follow the same predicate definition grammar as constraint rules. The operands in constraint macros can be variables rather than fixed values, as they are in constraint rules. The variables in a macro are substituted when the macro is invoked. For example, you can define a macro to compare patient names ( patientName == $NAME ). When this macro is invoked, the parameter NAME is assigned the value "Joe Smith" and the macro is transformed into the predicate:( patientName == "Joe Smith"). As another example, you can define a macro to check if a DICOM attribute is a code sequence attribute. A code sequence attribute must contain the mandatory child attributes, code value and code scheme. This macro checks whether the specified code sequence attribute contains these mandatory child attributes. A subset of Code Sequence Macro defined in DICOM standard, PS3.3-2007, Table 8.8-1 CodeAttr Code value must not be empty ${CodeAttr}.00080100 Code scheme designator must not be empty ${CodeAttr}.00080102 You can separate a constraint definition into multiple files. Each file defines one or more constraint rules or macros. A file can import the macros and constraint rules that are defined in a difference file. You must specify the set of external rules or macros before referencing them in a file. EXTERNAL_RULE_INCLUDE and EXTERNAL_MACRO_INCLUDE statements serve this purpose. Structure Overview Question mark "?" means optional items. Plus "+" means one or more items. Asterisk "*" means zero or more items. CONFORMANCE_CONSTRAINT_DEFINITION DOCUMENT_HEADER? DOCUMENT_CHANGE_LOG+ DOCUMENT_MODIFIER DOCUMENT_MODIFICATION_DATE DOCUMENT_VERSION? MODIFICATION_COMMENT? BASE_DOCUMENT? BASE_DOCUMENT_RELEASE_DATE? BASE_DOCUMENT_DESCRIPTION? EXTERNAL_MACRO_INCLUDE* EXTERNAL_RULE_INCLUDE* (GLOBAL_MACRO|GLOBAL_RULE)+ GLOBAL_RULE (name) | PREDICATE_DEFINITION (name) DESCRIPTION? PREDICATE_DEFINITION* PREDICATE+ ACTION (when, action)* GLOBAL_MACRO (name) DESCRIPTION? PARAMETER_DECLARATION+ PREDICATE_DEFINITION* PREDICATE+ ACTION (when, action)* PREDICATE DESCRIPTION? (LOGICAL|RELATIONAL|BOOLEAN_FUNC|INVOKE_MACRO|PREDICATE_REF|GLOBAL_RULE_REF) ACTION (when, action)* LOGICAL(operator) PREDICATE+ RELATIONAL(operator) (ATTRIBUTE_TAG|FUNCTION)(ATTRIBUTE_TAG|STRING_VALUE|XML_VALUE|FUNCTION)+ BOOLEAN_FUNC(operator) (ATTRIBUTE_TAG|STRING_VALUE|XML_VALUE|FUNCTION)* INVOKE_MACRO MACRO_NAME PARAMETER+ NAME VALUE FUNCTION(operator) (ATTRIBUTE_TAG|STRING_VALUE|XML_VALUE|FUNCTION)* A constraint document defines groups of predicates to validate the conformance of a DICOM content or a DICOM metadata document. A predicate group is the logical AND of a collection of predicates or predicate groups. Each predicate group has a name that is unique within its parent. Any other predicates can reference this predicate group by its name. The value of the reference is the Boolean of the predicate group. Optionally, a predicate group can contain a set of predicate definitions. These definitions are not part of the logical AND component of the predicate group, but they are meant to be referenced within the predicate group. A predicate group has an optional action element that specifies what action to take when the predicate evaluates to true or false. A type to specify an action for a predicate value. The "when" attribute specifies the predicate value. The "action" attribute specifies the type of action. When the action type is "log", "warning", or "error", the string value of this attribute is returned in a log file or as part of warning or error message. A derive B ( (NOT A) OR B ) gt greater than ge greater than or equal to lt less than le less than or equal to eq equal to ne not equal to in value in the set of match attribute value matches pattern The second operand must be a Java regular expression pattern as specified by JDK1.5 java.lang.String class documentation. Within the second operand, strings in the form "${...}" are interpreted as regular expressions rather than macro parameters. The first operand must be a DICOM attribute tag. The tag must identify an attribute that belongs to one of the following value representation types: AE, AS, AT, CS, DA, DT, LO, LT, PN, SH, ST, TM, UI and UT Note that the operands must be compatible with each other when a predicate invokes relational operator. For example, (patientAge > 005M) is a valid predicate. But (patientAge > "Joe Smith") is not a valid predicate, because the operand "Joe Smith" cannot be cast into an instance of the patient age attribute. To allow future extensions, the set of allowed operators for Boolean function types are not fixed. Operator names are case-sensitive. The current values for this operator are: "notEmpty", "occurs", "true", and "false". "occurs" takes a single operand ATTRIBUTE_TAG, and returns true if an attribute matching the tag exists. (The attribute value can be an empty string or null. For example, a DICOM type 2 attribute may be empty.); Otherwise, it returns false. "notEmpty" takes a single operand ATTRIBUTE_TAG. It returns true if an attribute matching the tag exists in a DICOM content and has a non-null value (e.g. a DICOM type 1 attribute); otherwise, it returns false. "true" takes no operand and it always returns true. "false" takes no operand and it always returns false. To allow future extensions, the set of allowed operators for function types are not fixed. Operator names are case-sensitive. This feature is not supported for Oracle Database 11g Release 1.