A Data Collection Matrix maps study objectives to variables and collection points.
Example:
| Variable | Screening | Enrollment | Day 7 | Day 28 |
| Age | ✓ | |||
| Sex | ✓ | |||
| Weight | ✓ | ✓ | ✓ | ✓ |
| Temperature | ✓ | ✓ | ✓ | |
| Outcome Status | ✓ |
This matrix helps:
- Avoid duplicate collection
- Identify missing variables
- Support database design
- Facilitate monitoring
Many experienced data managers create the matrix before developing CRFs.