What is it? Why is it important?

An interim database (eCRF) lock (IL) is performed before all data has been collected. It is mainly due to:

  • Specification defined in the study protocol due to safety or efficacy concerns. Planning an interim analysis during study conduct allows researchers to control for these risks. Requests for an interim analysis during study conduct might also be forwarded by the DSMB and/or EC.
  • Data cleaning processes during long term studies

 

Safety and efficacy information provided by the interim analysis will help to determine whether the study should be continued, adapted or terminated.

 

Data analysis not based on specifications in the study protocol carries the risk of corrupting the study, as the researcher is no longer an independent bystander but become biased as to study outcome of the study.

What do I need to do?

As a SP-INV in collaboration with the Data Manager (DMan) and Statistician:

  • Follow IL timelines as defined in the study protocol
  • Inform participating study sites of an upcoming IL, including the expected duration of the lock
  • Ensure IL procedures (e.g. defined in collaboration with the DMan in a SOP or WI ) are complied with, such as:
    • Data cleaning and query resolution are finalised before IL
    • Correct intermediate data export procedures for transfer to a statistical software system
    • Data remains blinded to the SP-INV and statistician during data evaluation

 

Database locks during study conduct can put increased pressure on site staff and people involved in data collection and management. In order to ensure data quality at the time of IL, train and remind staff to enter data consistently and in a timely manner.

Where can I get help?

Your local CTU can support you with experienced staff regarding this topic

References

ICH GCP E6(R2) – see in particular guidelines

  • 5.5. Trial Management, data handling, and record-keeping
Abbreviations
  • CTU – Clinical Trials Unit
  • DMan – Data Manager
  • DSMB – Data Safety Monitoring Board
  • EC – Ethics Committee
  • ICH GCP – International Council for Harmonisation - Good Clinical Practice
  • IL – Interim Lock
  • SOP – Standard Operating Procedures
  • SP-INV – Sponsor Investigator
  • WI – Working Instructions
Conduct ↦ Data Handling ↦ Data Handling ↦ Interim Lock
Study
Basic

Provides some background knowledge and basic definitions

Basic Protocol
Basic Statistics
Basic Monitoring
Basic Drug or Device
Concept

Starts with a study idea

Ends after having assessed and evaluated study feasibility

Concept Protocol
Concept Statistics
Concept Drug or Device
Development

Starts with confidence that the study is feasible

Ends after having received ethics and regulatory approval

Development Protocol
Development Statistics
Development Drug or Device
Set-Up

Starts with ethics and regulatory approval

Ends after successful study initiation

Set-Up Protocol
Set-Up Ethics and Laws
Set-Up Statistics
Set-Up Quality and Risk
Set-Up Drug or Device
Conduct

Starts with participant recruitment

Ends after the last participant has completed the last study visit

Conduct Protocol
Conduct Statistics
Conduct Drug or Device
Completion

Starts with last study visit completed

Ends after study publication and archiving

Completion Protocol
Completion Statistics
Completion Drug or Device
Current Path (click to copy): Conduct ↦ Data Handling ↦ Data Handling ↦ Interim Lock

Please note: the Easy-GCS tool is currently under construction.