What is it? Why is it important?

Working instructions (WIs) are documents that clearly and precisely describe how to perform a particular task. Their application are especially important in tasks where deviations can result in some undesirable consequence or even damage.



  • Are hand-on instructions, frequently needed during daily work (e.g. instructions on blood sampling and processing, how to conduct a study visit)
  • Are flexible, able to easily adapt to changing circumstances and requirements. As a consequence WIs:
    • Are reviewed on a regular basis
    • Have a simplified review and release process (e.g. compared to SOPs)
  • Ensure performance of study tasks are harmonised as well comparable between participating study sites


Apart from SOPs and WIs, other useful study documents exist such as templates, logs, checklists and forms. All these documents have important supportive character that give guidance to study staff involved in various responsibilities.

What do I need to do?

As a SP-INV:

  • Develop WIs applicable to your study:
    • Include test phases to ensure WIs correctly mirror process steps (e.g. especially important for the documentation of complex processes)
    • Ensure WIs are user friendly (e.g. validated in a test phase)
    • Write preferably in a local language to avoid misunderstandings
  • Provide Site-INV(s) with study relevant WIs
  • Incorporate WIs in the study DMS
  • During study conduct, request feedback regarding inconsistencies including performance difficulties
  • Implement WI adaptations as soon as they become known


As a Site-INV:

  • Train study staff on the SP-INV provided WIs
  • Ensure the SP-INV pre-approves locally devised WIs
  • Implement local WI adaptations as soon as they become known, and inform the SP-INV


Study staff:

  • Provide feedback on implemented WIs regarding inconsistencies, impossibilities and errors


In order to keep track of all study relevant documents include them in a study relevant DMS. This will guarantee:

  • Ongoing oversight of WIs, including other study documents, implemented in the study
  • The identification, tracking and management of study documents (e.g. current and approved versus archived documents)
  • Ensure only approved documents remain in circulation. This is especially important as various different staff members might perform a particular study task (e.g. potentially creating document chaos)

Where can I get help?

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

  • CTU – Clinical Trials Unit
  • DMS – Document Management System
  • Site-INV – Site Investigator
  • SOP – Standard Operating Procedure
  • SP-INV – Sponsor Investigator
  • WI – Working Instruction
Basic ↦ Documents ↦ Working Instructions ↦ Purpose

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): Basic ↦ Documents ↦ Working Instructions ↦ Purpose

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