What is it? Why is it important?

Based on the planned target population, it is crucial that its composition is taken into consideration when assessing the risk-benefit ratio of the study (e.g. health / disease status, vulnerable population such as children, pregnant women).


Study risks and burdens include:

  • Unwanted (serious) side effects related to the intervention or its procedures
  • The new treatment is not as effective as intended, or is not better than a standard treatment, and/or has more side effects
  • Impairment in the quality of life


Benefits include:

  • Efficacy of study treatment
  • Access to novel treatment options
  • Close monitoring with more frequent health check-ups
  • Psychosocial benefits (e.g. play a more active role in personal health care)
  • Ability to contribute to medical research that may save future lives, or improve the health of future patients


For interventional studies, the Swiss law provides clear risk-benefit guidelines for the use of placebo groups.

In studies with an expected direct benefit, the use of a placebo or non-treatment is only allowed if:

  • No additional risk of serious or irreversible harm is to be expected, and
  • No standard treatment is available; or
  • The use of a placebo is required for compelling, scientifically sound methodological reasons, in order to establish the efficacy or safety of a treatment method

What do I need to do?

As a SP-INV define potential risks and benefits for participants during study conduct.


  • Type of risks (e.g. are they serious or non-serious)
  • Risk detection methods (e.g. specific symptoms, lab reports)
  • Likelihood of risk occurrence (e.g. expected frequency)
  • Severity of risks (e.g. mild, moderate, severe)
  • Risk duration (e.g. a rash that lasts one week is more acceptable than if it lasts for one month or longer)
  • Reversibility of risks

Include potential psychosocial risks and/or quality of life impairments.


For benefit assess:

  • Type of expected benefit (e.g. pain reduction, a decrease in occurrence and duration, better quality of life)
  • Psychosocial benefits or the importance of the study for future patients.

Document expected study risks in the:


For more information refer to Quality & Risk in this study guide.


It is the responsibility of the SP-INV and Site-INV to ensure participants understand risks involved in study participation.

A shift in the study risk-benefit ratio (e.g. new risks) potentially affecting study participants requires that:

  • The SP-INV implements respective PIS updates
  • The Site-INV informs participants about new risks, and if applicable, asks the participant to re-consent to study participation

Changes to PIS and ICF documents require prior EC approval.

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, 7-9, 14 General principles
  • 16-18 Risks, burdens and benefits

Swiss Law

HRA – see in particular articles

  • Art. 8 Right to receive information
  • Art. 12 Risks and burdens
  • Art. 13 Placebo
  • Art. 15 Safety and protective measures
  • Art. 16 Informed consent risks

ClinO – see in particular articles

  • Art. 7 Information
  • Art. 8 Exception to written form
  • Art. 9 Consequences of revocation to consent
  • Art. 25 EC review areas
  • Art. 32 RA review areas

ClinO-MD – see in particular articles

  • Art. 3 lic. b Applicable provision
  • Art.11 EC review areas
  • Art. 17 RA review areas

HRO – see in particular articles

  • Art. 7 Categorisation
  • Art. 8 Information
  • Art. 9 Exceptions to written form
  • Art. 10 Consequences of revocation of consent


  • ClinO – Clinical Trials Ordinance
  • ClinO – MD – Ordinance for Clinical Trials with Medical Device
  • CTU – Clinical Trials Unit
  • EC – Ethics Committee
  • HRA – Human Research Act
  • HRO – Human Research Ordinance
  • ICF – Informed Consent Form
  • PIS – Participant Information Sheet
  • RA – Regulatory Authorities
  • Site-INV – Site-Investigator
  • SP-INV – Sponsor-Investigator
Concept ↦ Safety ↦ Safety in Studies ↦ Participant Risk-Benefit

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): Concept ↦ Safety ↦ Safety in Studies ↦ Participant Risk-Benefit

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