What is it? Why is it important?

The planning of data collection include the:

  • Definition of all variables that need to be collected in the study in order to answer the research question
  • Timing of when, which variables (data) must be collected during study conduct (i.e. which variable do I need to collect at baseline, visit 1, 2 …, end of study)
  • Methods used for data collection (e.g. blood draw, participant questionnaires, interview regarding medical history, x-rays)

 

Type of study variables include:

  • Primary outcome(s) (also referred to as endpoint(s)): Considered the most important variable of interest
  • Secondary outcomes: Additional variables monitored during study conduct
  • Safety outcome : Negative events experienced by study participants
  • Other outcomes: Variables that do not fit the above classifications
  • Predictor variable: Can potentially affect study outcome(s) variables
  • Confounding variable: May lead to the misinterpretation of study results
  • Population variables: Describe the study population

More

Variables should be collected that provide a description of the study population. This should include information about the study participants (e.g. demographic, clinical, social), as well as any particular characteristics that may be predictive of the study outcome (e.g., health status at baseline).

What do I need to do?

As a SP-INV:

  • Decide which variables are needed to answer your study question
  • Consult with a statistician to ensure study variables are correctly defined and available for the statistical analysis of your study (i.e. outcome -, predictor - , confounding -, population descriptive variables)  
  • Consult with a data manager to ensure the complete and correct documentation of your study data (e.g. important information is not missed)

 

When planning data collection, establish procedures to ensure ongoing data quality (e.g. SOPs, WIs). This will guarantee that data is correct and complete.

 

Aspects include:

  • To have an appropriate study design, where study visits occur at the time when study data (i.e. outcome variable(s)) must be collected and assessed
  • The availability of resources needed to measure and document study outcome(s) (e.g. CT scan, radiologists diagnosing scans) 
  • The availability of study staff trained on data collection and documentation (e.g. how to enter data in the study database)

Where can I get help?

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

References

ICH Topic E9 – see in particular

  • 2.1.1 Development Plan
  • 2.2.1 Population
  • 2.2.2 Primary and Secondary variables
  • 2.2.5 Multiple primary variables
  • 2.2.6 Surrogate Variables
Abbreviations
  • CT – Computed Tomography
  • CTU – Clinical Trials Unit
  • ICH – International Council for Harmonisation
  • SOP – Standard Operating Procedures
  • SP-INV – Sponsor Investigator
  • WI – Working Instructions
Basic ↦ Statistic Methodology ↦ Data Collection ↦ Planning
Study
Basic

Provides some background knowledge and basic definitions

Basic Monitoring
Basic Drug or Device
Concept

Starts with a study idea

Ends after having assessed and evaluated study feasibility

Concept Statistic Methodology
Concept Drug or Device
Development

Starts with confidence that the study is feasible

Ends after having received ethics and regulatory approval

Development Drug or Device
Set-Up

Starts with ethics and regulatory approval

Ends after successful study initiation

Set-Up Ethics and Laws
Set-Up Statistic Methodology
Set-Up Quality and Risk
Set-Up Drug or Device
Conduct

Starts with participant recruitment

Ends after the last participant has completed the last study visit

Conduct Statistic Methodology
Conduct Drug or Device
Completion

Starts with last study visit completed

Ends after study publication and archiving

Completion Statistic Methodology
Completion Drug or Device
Current Path (click to copy): Basic ↦ Statistic Methodology ↦ Data Collection ↦ Planning

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