TIME: data time stamp
The TIME columns define the time at wich dose and observation events occurred. When no DATE/DAT1/DAT2/DAT3 column is present, the time represents the time elapsed. When a DATE/DAT1/DAT2/DAT3 column is present, it represents the time of the day. The time can be defined using a double, or a clock format hh:mm or hh:mm:ss. Negative time values are allowed. When the double format is used, and no DATE/DAT1/DAT2/DAT3 column is present, the time has no predefined units. In all other cases, the time units are hours.
When a subject has time under the clock format, all times are converted into relative hours, as on the following example:
| TIME | Reconstructed time | ||
| 10:00 | 10 | ||
| 10:30 | 10.5 | ||
| 14:00 | 14 | ||
| 08:59 | 8.983333 |
When there is no column-type TIME, the column-type DATE is ignored, and the first column-type REGRESSOR is used as time. If no columns are tagged as REGRESSOR, time will be equal to the index of row number containing observations / amounts for each subject-occasion.
Format restrictions
- A data set shall not contain more than one column with the column-type TIME.
- If the TIME column-type is used, the TIME must be defined for all lines.
- String “.” will not be interpreted as a repetition of the previous line and is non-compliant with formats listed here-above.
DATE/DAT1/DAT2/DAT3: date information
The DATE column-type can be used to indicate the date of the dose or observation event. It is usually used in combination with the TIME column-type, which in that case indicates the time of the day. To accommodate the different date formats, several column types are possible:
| DATE | DAT1 | DAT2 | DAT3 | |
|---|---|---|---|---|
| Day, month and year | mm/dd/yy or mm/dd/yyyy
mm-dd-yy or mm-dd-yyyy |
dd/mm/yy or dd/mm/yyyy
dd-mm-yy or dd-mm-yyyy |
yy/mm/dd or yyyy/mm/dd
yy-mm-dd or yyyy-mm-dd |
yy/dd/mm or yyyy/dd/mm
yy-dd-mm or yyyy-dd-mm |
By default, when the year is coded with two digits, it is interpreted as 20xx.
Format restrictions
- A data set shall not contain more than one column-type DATE / DAT1 / DAT2 / DAT3.
- Year, day, and month shall be integers.
- The separator must be “/” or “-“
- Character “.” will not be interpreted as a repetition of the previous line and is not compliant with the DATE formats.
- All the lines should be filled correctly within the same delimiter, according to the specified date format: i.e., no empty year, no empty month, no empty day, no mix of delimiters.
Timestamp summary
There are several ways to define the timestamp of the data set depending if there is a TIME column or not and if there is a DATE column or not.
| TIME column present | TIME column not present | |
| DATE column present | DATE column is considered to represent the day and the TIME column the hour within this day | Date column ignored (regressor or index used) |
| DATE column not present | TIME column is considered to represent the time (no specific units) | First regression-column will be used to timestamp data |
FAQ
- My data is not “over time”, what should I do? You can arbitrarily set the time of each observation to 0.
- What happens if neither TIME nor DATE is defined? We strongly encourage the user to explicitly define the TIME column-type. However, if there is neither TIME nor DATE column-types, the first regression-column (i.e. first column with column-type REGRESSION) will be used to timestamp data. Moreover, if there is no TIME, no DATE and no REGRESSION column-type, time is equal to row indexes of each subject-occasion.
