Institutional Review Boards and ethics reviews
Each DSS should be attached to an Institution with a committee that would be tasked with reviewing the research proposal, consent forms, information sheets and any other relevant document (budgets, data collection tools) to be used in the study, ensuring that the rights, safety and well- being of study subjects are protected, the study design is appropriate and that there is scientific value attached to the proposal.  Initial submission usually follows schedules as proposed by the IRB/SEC, and any reactions by the committee must be answered by the Principal Investigator, before approval is provided. The proposal is submitted after funding has been received.
Once the proposal/protocol has been approved and activities resume, any amendments to the study documents, (proposal, consent forms, information sheet) must be submitted to the IRB/SEC for approval before being used.  
The IRB/SEC is expected to receive annual progress reports from the PIs with requests for continuation of the study for another twelve months.
All approvals by the IRB/SEC need to be submitted to the National Council of Science (or the national umbrella body of the IRB/SEC) for approval before study activities are initiated.
For clinical trials and intervention studies with adverse event and protocol violation reporting requirements these need to be submitted to the IRB/SEC within a specified time schedule. 
These committees do meet at given intervals (usually once a month). During the meetings the PI may be invited to answer queries in real time.
See also Informed consent in Section 3.