Censoring mechanism review
==========================

StatMedAnalysis | Original downloadable worksheet | 6 November 2026

Document why follow-up ends and what the censoring assumptions require.

How to use this worksheet
Separate administrative study end from loss to follow-up, treatment change and competing
events. Summarize reasons by group using aggregate counts. State the analysis estimand
and which unobserved outcomes would matter after censoring. Identify measured predictors
of loss and planned sensitivity analyses.

Save a working copy and keep the original blank version. Use public, hypothetical or
aggregate information only; do not enter patient identifiers, credentials or confidential
records. Keep source evidence in your approved project workspace. Mark unresolved text
fields UNKNOWN or NOT REPORTED with a reason; never substitute zero for an unknown count.

Project/version __________________  Prepared by role/date __________________

Working fields
1. Outcome and follow-up horizon
Response/evidence: _________________________________________________________
___________________________________________________________________________

2. Administrative cutoff rule
Response/evidence: _________________________________________________________
___________________________________________________________________________

3. Other censoring categories
Response/evidence: _________________________________________________________
___________________________________________________________________________

4. Reason counts by group
Response/evidence: _________________________________________________________
___________________________________________________________________________

5. Association with prognosis or treatment
Response/evidence: _________________________________________________________
___________________________________________________________________________

6. Measured predictors and timing
Response/evidence: _________________________________________________________
___________________________________________________________________________

7. Proposed censoring assumption
Response/evidence: _________________________________________________________
___________________________________________________________________________

8. Sensitivity analysis or alternate estimand
Response/evidence: _________________________________________________________
___________________________________________________________________________

Hypothetical worked case
In a fictional study, patients who worsen transfer to another provider and cease
contributing records. Labeling their last visit as censoring does not make their
subsequent event risk comparable to people who remain observed.

Decision rule and limitations
Do not treat a competing event as ordinary independent censoring without checking the
target quantity. Explain what would make loss informative and how the analysis addresses
that possibility.

Decision _______________________  Remaining uncertainty ____________________
Next action ____________________  Owner / review date ______________________
Independent check and discrepancy resolution _______________________________

Official method or reporting reference checked 6 November 2026
https://miguelhernan.org/whatifbook

This is an original planning aid, not an official checklist, validated instrument,
clinical recommendation or certificate of expert approval. Apply the referenced
guidance to the specific design and record any additional requirements.