Recording deviations
By the end of this lesson
- Identify a meaningful departure from the plan
- Record what changed and which work it affected
- Preserve planned and actual treatments separately
See it
A deviation is any meaningful difference between the planned protocol and what actually happened. Recording deviations protects the value of the experiment because later results can be interpreted in light of those differences.
Understand it
Identify a meaningful departure from the plan
Record what changed, when, why, and who made the change.
A deviation concerns the actual workflow or treatment differing from its planned form.
Record what changed and which work it affected
Do not overwrite the original plan.
These details make the difference reconstructable and connect it to the work performed.
Preserve planned and actual treatments separately
Connect deviations to affected batches and outcomes.
Preserving plan and actual event distinguishes intention from what was tested.
Worked example
During preparation, an operator uses a different stock than planned. Keep the original plan, record the actual stock and reason, and link the deviation to affected batches. Later results can then be interpreted against the treatment that actually occurred.
Explain your decision before opening the worked reasoning below.
Show the worked reasoning
The link establishes relevant context without automatically proving that the deviation caused a later response.
A record can look precise while hiding a meaningful treatment difference, weakening interpretation and reproducibility.
An undocumented deviation can turn an apparently precise experiment into ambiguous evidence.
Try it
How should the example's original plan be handled?
Use the worked example above to explain your answer in your own words before taking the quiz.
Lesson quiz
Assessment version: 2026-10-15-v2. Previous reading-completion markers are retained. This revised quiz has its own result.
Apply it
Use the worked example to write a short decision record: what did you observe, which rule did you apply, and what would you check before acting?
Completion marks reading progress, not a quiz pass or professional certification.