What is it? Why is it important?

During study conduct, the monitor checks the quality and integrity of the study data.

With respect to DM responsibilities, the monitor:

  • Checks whether data entry is correct and recorded in a timely manner
    • Recorded entries in the database correspond to SD (original data entries)
    • Data entries are done in close proximity to participant visits
  • Writes queries in the event of data inconsistencies or errors
  • Supervises query resolution by study site
  • Reports any inconsistencies to the SP-INV in order to define applicable corrective actions
  • Checks upon subsequent monitoring visits the implementation of any outstanding corrective actions


The requirement for study monitoring is based on regulatory requirements defined according to study type (ClinO or HRO) and risk category (A low risk, B or C high risk).

The SP-INV decides on the:

  • Frequency and type of monitoring (e.g. one or several spaced monitoring visits, on-site or central monitoring)
  • The extent of monitoring (e.g. what data to check) and scope of data to be monitored (e.g. all collected data, only a given percentage of data)

The MP of the study must be submitted for approval to the EC prior to study start. This includes any subsequent changes or adaptations thereof.

What do I need to do?

Based on study risk and complexity make yourself familiar with the monitoring requirements of your study and how it affects DM aspects.

Topics to evaluate are:

  • The management of monitor access to study data and the maintenance of data protection aspects (e.g. the monitor acts on behalf of the study SP-INV and is not granted access to participant identifiers at a given study site)
  • Documentation of query management (e.g. upload of query questions, query handling by study site, query resolution or pending issues)

For more information refer to Monitoring in this Study Guide.


Planned study monitoring activities are summarised in the MP of the study. It describes the monitoring strategy by defining scope, frequency and type of monitoring.

Where can I get help?

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


ICH GCP E6(R2) – see in particular guidelines

  • Art. 1.38 Monitoring
  • Art. 5.5 Trial Management, data handling, and record-keeping
  • Art. 5.18 Monitoring activities

Swiss Law

ClinO – see in particular article

  • Art. 5 Rules of Good Clinical Practice.


  • ClinO – Clinical Trials Ordinance
  • CTU – Clinical Trials Unit
  • DM – Data Management
  • EC – Ethics Committee
  • HRO – Human Research Ordinance
  • MP – Monitoring Plan
  • SD – Source Data
  • SP-INV – Sponsor-Investigator
Concept ↦ Data Handling ↦ Stakeholders ↦ Monitor

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): Concept ↦ Data Handling ↦ Stakeholders ↦ Monitor

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