The Stability of a Data-Field or Archive describes how 'fixed' the values are. There are four categories:
- Complete - all data has been collected and will never change, an example would be the date at which a participant joined the MCPS;
- Updateable - all data has been collected, but the values may change over time, an example would be the vital status of the participant as updated follow-up data is obtained;
- Accruing - data is still being gathered;
- Ongoing - data is still being gathered and the values already held may change over time;
- Obsolete - data which has been superceded by other fields and is not recommended for use.