Completion↦Management↦Study Closure↦Database Lock
What is it? Why is it important?
Database Lock (DL) is an action taken by the SP-INV upon study completion. The aim is to prevent unauthorized or unintentional changes to the study data after completion of data entry.
The DL is performed once:
- All study data are entered into the study database
- Open issues during data review, (e.g. data queries) are answered by the study site and considered resolved by the SP-INV
- Site-INV and/or SP-INV confirm that data is complete and correct
A final DL is faster if interim locks have already been performed during study conduct. Once the database is locked the data can be exported for statistical analysis.
More
Intermittent database locks allow the SP-INV to evaluate and analyse the data in the framework of an interim analysis to decide whether:
- It is worthwhile to continue the study, (e.g. intervention shows no expected effect)
- The study must be stopped due to ethical concerns, (e.g. treatment group performs significantly better than placebo or control group)
- The study must be stopped due to serious safety concerns in the treatment group compared to control group or placebo / comparator group
What do I need to do?
As a SP-INV in collaboration with a data manager:
- Set-up well-defined processes for database lock
- In a multi-centre study, study sites might close their study at different time points. This must be well managed and coordinated as a “global” lock will only be performed once all sites meet closing criteria
- Document the exact timing when the database was locked, to prove that:
- Statistical analysis took place after the database was locked
- Unblinding of your randomised blinded study was broken after database lock
Database lock should follow procedures defined in the data management plan.
More
To facilitate database lock, plan and ensure that:
- Data colletion is performed on an ongoing basis, while data is still “fresh”. Retrospective entry of large volumes of data carries increased quality risks
- External data providers (e.g. laboratories) are informed regarding upcoming database lock to integrate their data into the main study database
- Adequate time for data review and resolution of data queries / findiings are given
- Site-INV(s) sign off any complete and correct data on an ongoing basis (interim locks), so as not to postpone this task to the very end
Where can I get help?
Your local Research Support Centre↧ can assist you with experienced staff regarding this topic
Basel, Departement Klinische Forschung (DKF), dkf.unibas.ch
Lugano, Clinical Trials Unit (CTU-EOC), ctueoc.ch
Bern, Department of Clinical Research (DCR), dcr.unibe.ch
Geneva, Clinical Research Center (CRC), crc.hug.ch
Lausanne, Clinical Research Center (CRC), chuv.ch
St. Gallen, Clinical Trials Unit (CTU), h-och.ch
Zürich, Clinical Trials Center (CTC), usz.ch
References
ICH GCP E6(R3) – see in particular guidelines
- 4.2.5 Data Transfer, Exchange and Migration
- 4.2.6 Finalisation of Data Sets Prior to Analysis
- 4.2.7 Retention and Access
ISO 14155:2020 Medical devices (access liable to cost) - see in particular sections
- 8.6 Documentation retention