Date of Measurement Data type
What is the Date of Measurement?
The Date of Measurement is the date when a biological sample was actually measured or analyzed in the laboratory, not when it was collected from the participant.
Why It Matters
- Data Quality: Measurements can degrade over time; knowing the measurement date helps assess data quality
- Batch Effects: Samples measured on different dates may have systematic variations
- Sample Age: Time between collection and measurement can affect results
- Reproducibility: Essential for replicating experimental conditions
Difference from Collection Date
| Date Type | Description |
|---|---|
| Collection Date | When the sample was collected from the participant |
| Measurement Date | When the lab analysis was performed |
| Upload Date | When the data was entered into the system |
Best Practices
- Record the exact date from laboratory instruments or logs
- Include timezone information if measurements span multiple locations
- For time-sensitive analyses, consider recording time of day as well
- Document any delays between collection and measurement
Usage in CMMI-DCC
- Quality Control: Identify samples measured after unusual delays
- Batch Analysis: Group samples by measurement date for analysis
- Trend Detection: Account for instrument drift over time
Related Terms
- Biofluid: The type of sample measured
- Experimental Method: The measurement technique used