Interim Locks and DSMBs

Interim Locks and DSMBs                   

Special consideration needs to be given to providing data for interim locks and DSMBs during the course of a study. It is crucial that the data provided for these milestones is as complete, accurate and up-to-date as possible because the outcome can have serious implications on the review and progress of the study. 

It is essential for data management to plan in advance the identification of key data, the level of cleaning required and agree timelines with the project team.  This strategic planning requires input and commitment from wider study team:

  • For electronic-data-capture studies, site personnel need to commit to entering the key data and responding to queries in a timely manner. For paper studies, CRFs must be completed and sent to the Data Entry department. Phastar work closely with the sponsor, clinical project managers and CRAs to provide assistance if required in database issues and ensure new user accounts are set up promptly.
  • Source document verification of key data must be completed in time for data management review and query resolution.
  • Coding and approval of medical terms and medications must take place and time for queries must be considered.   Phastar Data Management code and query data on an ongoing basis to ensure there is no backlog.
  • Serious Adverse Event (SAE) reconciliation between the clinical database and the pharmacovigilance database, allowing time for queries to be resolved.  We build in regular timelines throughout a study for reconciliation of SAEs.
  • Cut-off dates for data need agreement from the whole study team and sponsor approval
  • If external data is required, then timelines must be agreed with the external vendors for data transmission to allow sufficient time for data reconciliation and query resolution
  • Data must be provided to the statistics department to allow sufficient time for programming activities.   Phastar data management work together with the programming and stats team throughout a study, providing ongoing data transfers and regular meetings to discuss data issues.

Our data management staff have a great deal of experience in providing data for interim locks and DMCs.  A Lead Data Manager is assigned to each study and that person will have detailed knowledge of the database and will be involved in project discussions and protocol deviation meetings. Data are reviewed on an ongoing basis immediately after data entry and source document verification, ensuring any issues are highlighted and addressed at an early stage. Interim locks should be performed on clean, QC'd data. Our databases allow locking of data at a CRF form level which enables the key data within a visit to be cleaned and locked whilst allowing ongoing processing of other data to continue.  Sometimes an interim analysis is requested on draft or “dirty” data.  However, there is a difference between “dirty” data and missing/incorrect data and we prioritise the interim data for early review to ensure the data is as accurate and complete as possible prior to use. The status of the data delivered for interim analysis is comprehensively documented.