What is it? Why is it important?

The site Investigator (Site-INV) carries main responsibility for study set-up and conduct at a particular study site.

According to GCP, responsibilities include to:

  • Have the required qualification and expertise
  • Ensure qualification and training of site staff
  • Comply with specifications given in the study protocol (e.g. randomisation procedures
  • Submission to EC)
  • Inform study participants and obtain informed consent for study participation
  • Ensure ongoing participant safety and care
  • Adhere to safety reporting procedures
  • Ensure the quality and integrity of study data
  • Implement correct storage and use of IMP/MD
  • Provide for required infrastructure
  • Ensure current and complete document filing
  • Ensure correct handling and storage of biological material

The Site-INV must retain ongoing oversight of local study activities including its delegated tasks


If at a particular site, the study is conducted by a team of individuals, the Site-INV would be the responsible leader of the team. Thus, in these instances the Site-INV will be given the title Principal Investigator.

What do I need to do?

The Site-INV should:

  • Be familiar with legal requirements for Site-INV
  • Have GCP training for IMP studies
  • Have ISO 14155 training for MD studies
  • Have the required professional knowledge and scientific expertise
  • Exercise the applicable medical profession (e.g. medicinal product or transplantation studies)
  • In the event no medical profession is required exercise another profession (non-medical) for ClinO chapter 4 studies or studies performed under the HRO ordinance

Depending whether you are a SP-INV or Site-INV will highly affect types of obligations and responsibilities.


During study conduct, the Site-INV is responsible to:

  • Implement the study according to the current study protocol, GCP / ISO 14155 and applicable laws
  • Recruit study participants, provide applicable information and sign the ICF
  • Ensure ongoing recruitment of study participant proceeds according to timeline
  • Protect the rights, safety and well-being of study participants
  • Ensure study design and randomisation procedures are correctly followed
  • Guarantee the quality and integrity of study results collected at the study site
  • Follow and ensure risk control measures are implemented and effective
  • Forward safety issues to the SP-INV within required timelines
  • Handle IMP/MD according to SP-INV specifications
  • Manage study document with ongoing filing of essential documents (e.g. ISF)
  • Supervise delegated study-related tasks

Where can I get help?

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

External Links

Swissethics – see in particular

  • Information on professional qualifications
  • List of persons conducting a study


ICH GCP E6(R2) – see in particular guidelines

  • 1.34 Investigator definition
  • 4 Site-INV responsibilities

ISO 14155:2020 Medical devices - see in particular sections (access liable to costs)

  • 3.30 Investigator definition (Site-INV)
  • 3.39 Principal investigator definition (Site-INV)
  • 10 Responsibilities of the principal investigator (Site-INV)

Swiss Law

ClinO – see in particular articles

  • Art. 2 Definitions
  • Art. 6 Professional qualifications

HRO – see in particular article

  • Art. 4 Professional qualifications
  • ClinO – Clinical Trials Ordinance
  • CTU – Clinical Trials Unit
  • EC – Ethics Committe
  • HRO – Human Research Ordinance
  • ICH-GCP – International Council for Harmonisation - Good Clinical Practice
  • ISO – International Organization for Standardization
  • ICF – Informed Consent Form
  • IMP/MD – Investigational Medicinal Product / Medical Device
  • ISF – Investigator Site File
  • MD - Medical Device
  • Site-INV – Site-Investigator
  • SP-INV – Sponsor-Investigator
Development ↦ Management ↦ 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 Quality and Risk
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): Development ↦ Management ↦ Responsibilities ↦ Site-Investigator

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