Start Date Imputation Method
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Use this widget to specify whether to use the first moment rule or last moment rule for deriving missing values in the variable indicating the starting day of an event/finding/intervention.
This widget checks date information from the xxSTDTC variable and is used only when xxSTDTC is present and either day or month and day information is missing.
Imputation Method
When date/time values are either partial or incomplete, JMP Clinical enables you to choose to choose to invoke either a “first moment” or 'last moment' rule to handle partial dates. In these cases, when a date/time component is not included in the ISO 8601 value, that value is assumed to be the first or last possible value, depending on your selection.
If the imputation rule for partial date/time values is "First":
| • | if the time is missing, JMP Clinical imputes 00 missing hours, minutes, and seconds. |
| • | if the day is missing, JMP Clinical imputes the first day of the month. |
| • | if both the day and the month are missing, JMP Clinical imputes the first day of the first month (01-Jan). |
If imputation method for partial date/time values is "Last":
| • | if the time is missing, JMP Clinical imputes 23 hours, 59 minutes, and 59 seconds. |
| • | if the day is missing, JMP Clinical imputes the last day of that month. |
| • | - if both the day and the month are both missing, JMP Clinical imputes 31 for day and 12 for month (31-Dec). |
For example, you have chosen to use the first rule and the date value for an event is listed as “2013-12”. In this case, JMP Clinical assumes that the event occurred at 12:00 AM on the first day of December 2013. and assigns a time value of “00:00" and a day value of "01". The resulting sort order of partial dates using the first-moment rule is the same as that of the ISO 8601 strings themselves.