Landmark Analysis Explorer
Reset the survival clock at a landmark time to see how conditioning on survival-to-date changes the predicted curve and its eligible population.
- landmark analysis
- conditional survival
- dynamic prediction
- survival analysis
Baseline vs. landmark survival prediction
Baseline (from t=0)Landmark (conditional on T > s)
Risk set size over time
Eligibility at the landmark
Total patients
260.000
Eligible at s
223.000
Ineligible (event/censored before s)
37.000
S(s)
0.858
Prediction formula
| Symbol | Meaning | Current value |
|---|---|---|
| s | Landmark time | 1.0 yr |
| τ | Prediction window | 2.0 yr |
| Estimand | P(T > s + τ | T > s, H(s)) |
Conditioning changes the question, not just the curve
The baseline curve answers "survival from the moment of surgery." The landmark curve, reset to 1.0 at s and computed only from patients who survived to s, answers a different and often more relevant question for a patient sitting in front of you at their s-year follow-up: survival conditional on having already made it this far.