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Sometimes a form is nearly identical at every data collection point, but there is a slight difference in the question for some items. For example, at baseline the prompt is "what's your highest pain rating in the last two weeks?", whereas at follow-up, the prompt is "What's your highest pain rating since the last visit?" Note that the data entry prompt is part of the data definition (i.e., tied together with how the variable is defined , e.g., a number with the prompt "Age:") and each variable only has ONE prompt.
Often with only a slight change in the display prompt the statistician will prefer to keep the variable in the same column within the data set (option 1 below). This is done in study by either creating a second, non-exportable variable, that is only used for the display prompt and is shown/hidden when appropriate. Or the time reference is taken out of the prompt and put in a heading and the heading is shown/hidden when appropriate (e.g., one heading says, "The following question refer to in the past week", whereas the other heading says, "The following questions refer to since the last visit".
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