To avoid duplication and confusion amongst the data points collected in a study, certain identifiers and ordinal numbers must be appended to each variable name. These variable names can be used in multiple CRFs across multiple Events.
These appendages will help identify the event, CRF and item the value was collected in. The identifiers are defined in the header table for tab, HTML, and Excel formats. The identifiers are defined in a separate syntax (.sps) file for SPSS. The following scheme will be implemented:
E1 = E specifies that the appendage represents the event. 1 specifies which event the variable is from, as defined in the header table. If the event is repeating, it would be represented as E1_1, E1_2, E1_3 etc.
C1 = C specifies that the appendage represents a CRF. 1 specifies which CRF the variable is from, as defined in the header table
For repeating events and repeating groups, additional information must be provided to detail which occurrence of the event and/or which repeat of the group the item value comes from. This is done by appending _X where X is the ordinal or repeat number. As an example, an item called DEMO appearing in the 3rd occurrence of a repeating event, and the 5th repeat of the group called Example would be identified in the following way.
DEMO_E1_3_C1_5
For an item in a repeating event, but not part of a repeating group, the variable would be identified in the following way:
DEMO_E1_3_C1