What is it? Why is it important?

Essential Documents (ED) are documents collected prior-, during- and after study completion in order to demonstrate study staff compliance with the study protocol, GCP, and applicable regulatory requirements.

Based on essential documents:

  • Study set-up and implementation can be retraced from start to finish
  • Quality of study data can be evaluated
  • Protocol compliance can be assessed

Essential documents:

  • Are reviewed during study monitoring, SP-INV audit, or during regulatory inspection
  • Should only be accessible to study staff, study monitor, and if applicable auditors and inspectors


In order to track currency and revision of study documents, unique identifier should be given, such as:

  • Appropriate name related to its use
  • Date when the document was issued
  • Version number based on minor or major changes (e.g. 1.0, 1.1, 1.2, 2.0, 2.1)
  • Relevant author(s)
  • If applicable, staff that reviewed, approved, and released the document (e.g. study protocol, monitoring plan, study specific SOPs)

What do I need to do?

Based on the planned study, various essential documents must be generated and filed. ICH-GCP section 8 and ISO 14155, Annex E give a non-exhaustive overview of essential documents before-, during-, and after study completion.

Essential documents are filed in a:

  • Trial Master File (TMF): SP-INV documents
  • Investigator Site File (ISF): documents generated and filed at a particular study site

Essential documents can also include various check-lists, process-, SOPs and WIs needed for the faultless running of the study.


For more information refer to Documents in this Study Guide.

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

  • 1.23 Essential documents definition
  • 5.18.4p Monitoring responsibilities
  • 8.1-4 Filing of essential documents

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

  • Annex E Essential clinical investigation documents
  • CTU – Clinical Trials Unit
  • EC – Ethics Committee
  • ED – Essential Documents
  • ICF – Informed Consent Form
  • ICH-GCP – International Council for Harmonisation - Good Clinical Practice
  • ISF – Investigator Site File
  • ISO – International Organization for Standardization
  • SOP – Standard Operating Procedures
  • SP-INV – Sponsor-Investigator
  • TMF – Trial Master File
  • WI – Working Instructions
Development ↦ Management ↦ Study Documents ↦ Essential Documents

Provides some background knowledge and basic definitions

Basic Protocol
Basic Statistics
Basic Monitoring
Basic Drug or Device

Starts with a study idea

Ends after having assessed and evaluated study feasibility

Concept Protocol
Concept Statistics
Concept Drug or Device

Starts with confidence that the study is feasible

Ends after having received ethics and regulatory approval

Development Protocol
Development Statistics
Development Drug or Device

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

Starts with participant recruitment

Ends after the last participant has completed the last study visit

Conduct Protocol
Conduct Statistics
Conduct Drug or Device

Starts with last study visit completed

Ends after study publication and archiving

Completion Protocol
Completion Statistics
Completion Drug or Device
Current Path (click to copy): Development ↦ Management ↦ Study Documents ↦ Essential Documents

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