TQ2 - Timing/Quantity Relationship Segment

The TQ2 segment is used to form a relationship between the service request the TQ1/TQ2 segments are associated with, and other service requests. The TQ2 segment will link the current service request with one or more other service requests.

There are many situations, such as the creation of a service request for a group of intravenous (IV) solutions, where the sequence of the individual intravenous solutions (each a service in itself) needs to be specified, e.g., hyperalimentation with multi-vitamins in every third bottle.

There are other situations where part of the service request's instructions contains a results condition of some type, such as "PRN pain." There is currently a free text "condition" field of TQ1-10 - Condition text which allows any condition to be specified. However, to support a fully encoded version of service request sequencing, or results condition, the TQ2, Timing/Quantity Relationship segment has been defined.

HL7 Attribute Table - TQ2 - Timing/Quantity Relationship Segment

Seq#	Data Element Name	DataType	Usage	Vocabulary	Cardinality	Item #	Length	C.LEN	Flags
TQ2
1	Set ID - TQ2	SI	O		[0..1]	01648	[1..4]
2	Sequence/Results Flag	ID	O	0503(R) Sequence/Results Flag(Required)	[0..1]	01649	[1..1]
3	Related Placer Number	EI	C		[0..*]	01650
4	Related Filler Number	EI	C		[0..*]	01651
5	Related Placer Group Number	EI	C		[0..*]	01652
6	Sequence Condition Code	ID	C	0504(R) Sequence Condition Code(Required)	[0..1]	01653	[2..*]
7	Cyclic Entry/Exit Indicator	ID	C		[0..1]	01654	[1..1]
8	Sequence Condition Time Interval	CQ	O		[0..1]	01655
9	Cyclic Group Maximum Number of Repeats	NM	O		[0..1]	01656		10	#
10	Special Service Request Relationship	ID	C	0506(R) Service Request Relationship(Required)	[0..1]	01657	[1..1]

TQ2 Usage notes:

1. Cyclic placer service request groups

To implement a cyclic group of four IV service requests using the parent/child paradigm, the parent specifies a custom group of IVs, and the following occurs:

• • • TQ2 of the second child service request specifies that it follow the first child service request.

    • TQ2 of the third child service request specifies that it follow the second child service request.

    • TQ2 of the fourth child service request specifies that it follow the third service request.

To repeat the group of four child service requests in a cyclic manner, the following occurs:

• • • TQ2 of the first child service request specifies that it is to be executed once without any dependence on the completion of other service requests. Its second execution follows the completion of the fourth service request. See example in Section 4A.5.2 RXO segment field examples.

This scheme allows the following to be tracked:

• The status of the whole group of service requests to be reported back at the level of the parent service request.

• The status for each individual IV service request by following the status of the corresponding child service request.

Separate Service requests example:

• The same group of service requests can be sent as a group of four service requests (without a common parent), linked only by the data in their quantity/timing fields. In this case, there is no convenient HL7 method of transmitting the service request status of the group as a whole without transmitting the status of each of the four separate service requests.

• Inheritance of service request status

Cancellation/discontinuation/hold service request control events:

• • • This logic implies the normal execution of the referenced predecessor service request. Thus a cancel (or discontinuation or hold) of a predecessor service request implies the cancellation (or discontinuation or hold) of all subsequent service requests in the chain.

    • If the referenced service request has been canceled (or discontinued or held), the current service request inherits that same status.

    • In the case of hold, the removal of the hold of the predecessor implies a removal of the hold for the given service request (which can then be executed according to the specification in the TQ2 segment).

TQ2-1: Set ID - TQ2 (SI) 01648

Definition: For the first timing specification transmitted, the sequence number shall be 1; for the second timing specification, it shall be 2; and so on.

TQ2-2: Sequence/Results Flag (ID) 01649

Definition: This flag defines the sequencing relationship between the current service request, and the related service request(s) specified in this TQ2 segment. See HL7 Table 0503 – Sequence/Results Flag in Chapter 2C, Code Tables, for values. If not value is present, the S - Sequential is the default value.

TQ2-3: Related Placer Number (EI) 01650

Definition: The placer numbers of the service request(s) to which this TQ2 segment links the current service request. This field should be populated with the appropriate "Placer number" from the current service request. For orders, the Placer Order Number from ORC-2 is the appropriate "Placer number". Repeats of this field indicate the current service request is related to multiple service requests.

Conditional Rule: At least one of TQ2-3, TQ2-4, TQ2-5 must contain a value.

TQ2-4: Related Filler Number (EI) 01651

Definition: The filler numbers of the service request(s) to which this TQ2 segment links the current service request. This field should be populated with the appropriate "Filler number" from the current service request. For orders, the Filler Order Number from ORC-3 is the appropriate "Filler number". Repeats of this field indicate the current service request is related to multiple service requests.

Conditional Rule: At least one of TQ2-3, TQ2-4, TQ2-5 must contain a value.

TQ2-5: Related Placer Group Number (EI) 01652

Definition: The placer group numbers of the service request(s) to which this TQ2 segment links the current service request. This field should be populated with the appropriate "Placer group number" from the current service request. For orders, the Placer Group Number from ORC-4 is the appropriate "Placer group number". Repeats of this field indicate that the current service request is related to multiple groups of service requests.

Conditional Rule: At least one of TQ2-3, TQ2-4, TQ2-5 must contain a value.

TQ2-6: Sequence Condition Code (ID) 01653

Definition: Defines the relationship between the start/end of the related service request(s) (from TQ2-3, TQ2-4, or TQ2-5) and the current service request from ORC-2, 3 or 4. See HL7 Table 0504 – Sequence Condition Code in Chapter 2C Code Tables, for allowed values.

Conditional Rule: Either this field or TQ2-10 must be present.

TQ2-7: Cyclic Entry/Exit Indicator (ID) 01654

Definition: Indicates if this service request is the first, last, service request in a cyclic series of service requests. If null or not present, this field indicates that the current service request is neither the first or last service request in a cyclic series of service requests. Refer to HL7 Table 0505 – Cyclic Entry/Exit Indicator in Chapter 2C, Code Tables, for allowed values.

Conditional Rule: Should not be populated when TQ2-2 (Sequence/Results Flag) is not equal to a 'C' (cyclic service request).

Example of TQ2 - 6, 7, & 8 Usage:

Example	Translation
...|ES|*|+10^min|...	translates to: execute this service request the first time without evaluating the condition specified in the TQ2 segment; but repeat only its execution when the specified external service request's start or finish date/time has met this condition. This specification generates a repetition of the service request for each iteration of the cycle.

TQ2-8: Sequence Condition Time Interval (CQ) 01655

Definition: Defines the interval of time between the start/end of the related service request(s) and the start/end of the current service request. The unit's component is constrained to units of time. If this field is not populated, then there should be no interruption between start/ending the current service request, and the related service request(s).

TQ2-9: Cyclic Group Maximum Number of Repeats (NM) 01656

Definition: The maximum number of repeats for a cyclic group.

The total number of repeats is constrained by the end date/time of the last repeat or the end date/time of the parent, whichever is first. For example, if the total number or repeats is valued at 10 and the group has already repeated 5 times, the current order will not be repeated again if either the current order, or the prior order in the cycle, has reached its end date/time.

This field is meaningful only when TQ2-2 Sequence/Results Flag is valued with 'C'. However, even in this case this field is optional.

TQ2-10: Special Service Request Relationship (ID) 01657

Definition: This defines an additional or alternate relationship between this service request and other service requests. Its primary intended use is for Pharmacy administration service requests, but it may be useful for other domains. See HL7 Table 0506 – Service Request Relationship in Chapter 2C, Code Tables, for allowed values.

Conditional Rule: Either this field or TQ2-6 must be present.