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[colorblue:-1] → Value assumed for the variable “colorblue” is -1 if no response found in the dbdatabase.
[study_startdate:2100-01-01] → Value assumed for the variable “study_startdate” is 2100-01-01 if not value found.
[RadioQ1:0] → If no response found, the value for “RadioQ1” is assumed to be 0.
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