What is it? Why is it important?

During study conduct, the safety of study participants must be guaranteed at all times. Based on the safety laws, human studies:

  • Can only be carried out if equivalent findings cannot be obtained through other means
  • Must ensure that risks and burdens are minimised
  • Must ensure that risks and burdens are not disproportionate to any expected benefits (e.g. risk-benefit ratio)

The Ethics Committee (EC) and RA (e.g. Swissmedic) only approve studies that comply with these principles. Consequently, during study conduct:

  • Participant safety is constantly monitored (e.g. safety risk review)
  • Safety events are assessed and reported to EC/RA on an ongoing and timely required manner (e.g. safety reporting)
  • The risk-benefit ratio of the study is constantly monitored in order to remain acceptable (e.g. benefits outweigh risks)
  • The study is immediately stopped once safety can no longer be guaranteed


The risk-benefit assessment of an ongoing study requires that physical, psychological, and social risks are included in the evaluation. All aspects considered the potential individual benefit for participants must outweigh any identified risks.

What do I need to do?

As a SP-INV and Site-INV know and comply with safety:


As a SP-INV:

  • Set-up a risk-based Quality Management System (risk-based QMS) for your study
  • Assess the risk-benefit ratio of the study on an ongoing basis. Implement as applicable risk preventative measures
  • Immediately stop the study if participant safety can no longer be guaranteed


For more information refer to Safety and QM & Risk in this Study Guide.


Safety monitoring is a dynamic process. At any time during study conduct, can new and unexpected safety issues become apparent. In the event of new safety concerns, study participants must be informed on how this might affect their safety (e.g. orally and in writing such as a PIS). A protocol safety amendment might require that the Informed Consent Form (ICF) be adapted. In that case, participants are asked whether they want to stay in the study, and if so they are requested to re-consent to study participation (e.g. participant sign and date the updated ICF document).

Where can I get help?

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


Declaration of Helsinki – see in particular principles

  • 4 Safety
  • 7-9 Protection of rights, health and interest
  • 14 Medical research and medical care
  • 16-18 Risks, burdens and benefits

ISO 14155:2020 Medical device (access liable to costs) – see in particular sections

  • 4 Summary of GCP principles
  • 6.2 Risk management
  • 7.4.4 Risk assessment process for potentially unacceptable risks

SAMS manual “Research with human subjects” – see in particular chapters

  • Chapter 4 Scientific requirements
  • Chapter 6 Assessment of risk and benefits

Swiss Law

HRA – see in particular article

  • Art. 15 Safety and protective measures
  • CTU – Clinical Trials Unit
  • EC – Ethics Committee
  • EC/RA – Ethics Committee / Regulatory Authorities
  • GCP – Good Clinical Practice
  • HRA – Human Research Act
  • ICF – Informed Consent Form
  • ISO – International Organization for Standardization
  • RA – Regulatory Authorities
  • SAMS – Swiss Academy of Medical Sciences
  • Site-INV – Site Investigator
  • SOP – Standard Operating Procedure
  • SP-INV – Sponsor Investigator
  • WI – Working Instruction
Conduct ↦ Ethics and Laws ↦ Safety ↦ Requirements

Provides some background knowledge and basic definitions

Basic Monitoring
Basic Drug or Device

Starts with a study idea

Ends after having assessed and evaluated study feasibility

Concept Drug or Device

Starts with confidence that the study is feasible

Ends after having received ethics and regulatory approval

Development Drug or Device

Starts with ethics and regulatory approval

Ends after successful study initiation

Set-Up Ethics and Laws
Set-Up Quality and Risk
Set-Up Drug or Device

Starts with participant recruitment

Ends after the last participant has completed the last study visit

Conduct Drug or Device

Starts with last study visit completed

Ends after study publication and archiving

Completion Statistics
Completion Drug or Device
Current Path (click to copy): Conduct ↦ Ethics and Laws ↦ Safety ↦ Requirements

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