What is it? Why is it important?

The site investigator (site-INV) is responsible for participant protection and reliability of study results at a particular study site. The Site-INV must:

  • Follow risk procedures as defined by the SP-INV
  • Inform SP-INV regarding novel risk concerns
  • Evaluate and propose local mitigating risk measures
  • Ensure that local quality requirements are in place (e.g. local SOPs, WIs, processes)
  • Ensure that site staff is qualified and trained on risk management including additional quality aspects
  • Ensure that study conduct complies with protocol and risk management procedures


The Site-INV agrees to conduct the study as defined in the protocol and collect and document study data in a correct and timely manner.

What do I need to do?

Familiarise yourself with the role and responsibilities of the Site-INV, for example:

  • Regulatory and GCP requirements
  • Training requirements (e.g. protocol, local SOPs, GCP certificate)
  • Ensure site staff is qualified to perform study-related duties
  • Supervise any individual or party to whom study-related duties and functions have been delegated
  • Manage site risks and maintain oversight of the risk strategy of the study. Inform SP-INV of any problems
  • Timely filing of study documents (e.g. ISF)



The Site-INV must supervise delegated study tasks and ensure staff member are qualified by education and training to perform delegated tasks.

In additions, the supervision and efficiency of implemented risk mitigation measures must be assessed on an ongoing basis.

These procedures must be documented.

  • The SP-INV should be informed of any problems related to mitigating measures, as the risk strategy of the study might have to be adapted in order to keep its efficiency
  • Delegated tasks must be supervised (e.g. perform regular staff meetings where study updates, issues, problems and solutions can be handled and discussed). Document these meetings
  • Based on delegated tasks study members must be appropriately trained (e.g. document all relevant study training in applicable training logs. Include document(s) trained, name of trainer, trainee and date of training)

Remember, even though study tasks can be delegated by the site, final responsibility always remains with the Site-INV.

Where can I get help?

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


ICH GCP E6(R2) – see in particular guideline

  • 5.0 Quality management

ISO 31000 – see in particular section

  • Risk management (access liable to costs)
  • CTU – Clinical Trials Unit
  • GCP – Good Clinical Practice
  • ISF – Investigator Site File
  • Site-INV – Site-Investigator
  • SOP – Standard Operating Procedures
  • SP-INV – Sponsor-Investigator
  • WI – Working Instructions
Basic ↦ Quality and Risk ↦ Responsibilities ↦ Site-Investigator

Provides some background knowledge and basic definitions

Basic Protocol
Basic Statistics
Basic Monitoring
Basic Drug or Device
Basic Biobanking

Starts with a study idea

Ends after having assessed and evaluated study feasibility

Concept Protocol
Concept Statistics
Concept Drug or Device
Concept Biobanking

Starts with confidence that the study is feasible

Ends after having received ethics and regulatory approval

Development Protocol
Development Statistics
Development Drug or Device
Development Biobanking

Starts with ethics and regulatory approval

Ends after successful study initiation

Set-Up Protocol
Set-Up Ethics and Laws
Set-Up Statistics
Set-Up Drug or Device
Set-Up Biobanking

Starts with participant recruitment

Ends after the last participant has completed the last study visit

Conduct Protocol
Conduct Statistics
Conduct Drug or Device
Conduct Biobanking

Starts with last study visit completed

Ends after study publication and archiving

Completion Protocol
Completion Statistics
Completion Drug or Device
Completion Biobanking
Current Path (click to copy): Basic ↦ Quality and Risk ↦ Responsibilities ↦ Site-Investigator

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