Overview
Datasets that contain more than one observation per subject requires a variable to that documents the sequence number.  The name of this sequence variable is usually the name of the CDISC domain name followed by SEQ.  For example, adverse event would have an AESEQ variable.  The values of the sequence number are commonly integers which increment by one for each observation.  The ADDSEQ facility within CDISC builder will automatically create this sequence variable based on the selected related domain and other related variables.  This can be access by selecting ADDSEQ from the main CDISC Builder screen.

ADDSEQ Options
The ADDSEQ screen allows you to select all the options before applying the sequence number to the selected data. 

The options available for ADDSEQ include the following:

• Source Data - This is the location of the dataset that is going to have the sequence number added or updated.
• Data Set - The selected dataset that is going to be updated.
• Related Domain - The CDISC domain which this data is associated with.
• Identification Variable - A unique identifier that distinguishes the observation that is repeated for each subject within the dataset.
• Unique Subject ID - A variable related to the subject ID.
• Base Code - The path and name of the BASE SAS program that is going to be created to perform the ADDSEQ.
• Save Code - The code saved in this location will contain a macro call capturing all the options that has been selected.  This can therefore be executed independent from this interface as a SAS program.
• Find Sequence - This will generate a report of other datasets that has more than one observation per subject which would therefore require a sequence variable.

Only one dataset can be selected at a time to have ADDSEQ applied.  This is due to the fact that the identifying variable usually is different among each dataset and therefore has to be selected individually.