Completion↦Data Management↦Final Database Lock↦Procedures
What is it? Why is it important?
At the final database lock, actions are taken to prevent further changes to the study database. The final lock is performed at the end of the study once:
- All required study data has been collected and entered into the study database (eCRF)
- Data has been checked and corrected for missing and incorrect entries
- Data queries triggered by the study monitor have been resolved by study staff
- The SP-INV or Site-INV has signed off the eCRF, confirming data to be correct and complete
After final lock:
- Changes to the study database (eCRF) is no longer possible
- The locked data is ready for export and statistical analysis
More
In the event of a multi-centre study, respective locks must be performed or adapted based on study progression at individual study-sites. Some sites might complete data collection earlier than others. Thus, individual site-specific locks might precede the final global lock of the study.
Studies with large amounts of data, or lasting over long periods of time, might profit from Interim Locks (IL). An IL will:
- Reduce the amount of work during final lock
- Allow for data quality checks to be performed in close proximity of the originally collected and entered data
What do I need to do?
As a SP-INV in collaboration with the study Data Manger:
- Define well-structured procedures that must be followed during the final database lock in an SOP
- If applicable, make special provisions based on individual site-locks versus global-lock, where all databases in all study-sites are locked
- Inform sites ahead of time regarding final database lock in order for them to fiinalize data entry and data monitoring
- Document time and date of database lock to prove that:
- Statistical analysis took place after database lock
- If applicable, blinded randomisation codes were broken after database lock
Plan ahead in order to avoid chaos and facilitate database lock. Hindsight management of large volumes of data carries a significant risk to data quality including the confidence in study results.
More
In order to avoid chaos and facilitate database lock, plan ahead and ensure that:
- Study data is entered on an ongoing basis, while data is still “fresh”. The Site-INV can sign off data on an ongoing basis, so as not postpone this task to the very end
- External data providers (e.g. laboratories) are informed regarding upcoming locks. Through ongoing data import the main study database remains current and complete, significantly reducing import workload at final lock.
- The monitor is given adequate time for data monitoring and resolution of data queries
Where can I get help?
Your local CTU↧ can support you with experienced staff regarding this topic
Basel, Departement Klinische Forschung, CTU, dkf.unibas.ch
Lugano, Clinical Trials Unit, CTU-EOC, www.ctueoc.ch
Bern, Clinical Trials Unit, CTU, www.ctu.unibe.ch
Geneva, Clinical Research Center, CRC, crc.hug.ch
Lausanne, Clinical Research Center, CRC, www.chuv.ch
St. Gallen, Clinical Trials Unit, CTU, www.kssg.ch
Zürich, Clinical Trials Center, CTC, www.usz.ch
References
ICH-GCP E6(R2) – see in particular guidelines
- 5.5. Trial management, data handling, and record-keeping