Background

• Data in a clinical trial can be collected in a format that best suits the operational needs of the sponsor.
• However, the data needs to be standardized as per SDTM standard for submission to regulatory authorities
• Date and time values are frequently collected data points in a clinical trial, and there are multiple ways in which these can be represented
• As per SDTM standard, date and time values are to be represented in ISO 8601 standard in the SDTM datasets

What is ISO 8601 standard?

ISO 8601 is an international standard covering the worldwide exchange and communication of date and time-related data. 

How are date time values represented in ISO 8601 standard in SDTM?

• Date and time components are presented in a single variable of character data type
• Date and time are separated by a delimiter 'T'
• In the date component, Year, month, and day are separated by a hyphen in between
• Year is presented as 4-character wide string (YYYY) eg: 2010
• Month is presented in 2-character wide string (MM) eg: 12 (for December)
• Day is presented in 2-character wide string (DD) eg: 03 (for 3rd day of the month)
• Missing components are represented with a hyphen or right truncated
• In the time component, hour, minute and seconds are separated by a colon in between
• Hours are represented in 2-character wide sting in 24 hours format eg: 22 for 10 pm
• Minutes are represented in 2-character wide string eg: 02 for 2 minutes past an hour
• Seconds are represented in 2-character wide string eg: 09 for 9 seconds 

11:59:59 pm of 31st December 2010 is presented as  2010-12-31T23:59:59

What do we learn in this lesson?

• We will see how to programmatically convert the dates to ISO 8601 format