All examples · Example 28 of 34
Kaplan–Meier Survival Curve
Kaplan–Meier overall survival for standard care and the new therapy (n = 100 per arm) with 95% confidence bands and censoring; dashed lines mark median survival.
Key findings
- Deaths: 74/100 (Standard care) vs 55/100 (New therapy).
- Kaplan–Meier median survival 14.3 vs 23.1 months.
Events and follow-up
The share of patients who died during follow-up in each arm, with 95% Wilson intervals. These crude proportions ignore when the events happened — the Kaplan–Meier curves on the figure account for censoring.
Deaths during follow-up
| Proportion | Count | Estimate | 95% Wilson CI | 95% Wald CI |
|---|---|---|---|---|
| Standard care | 74 / 100 | 74.0% | 64.6% – 81.6% | 65.4% – 82.6% |
| New therapy | 55 / 100 | 55.0% | 45.2% – 64.4% | 45.2% – 64.8% |
LabTools calls (2)
stats.cilabtools stats ci --kind proportion --successes 74 --n 100 --method wilson
stats.cilabtools stats ci --kind proportion --successes 74 --n 100 --method wald
The same method is available as an MCP tool (stats_ci) and from the desktop app's statistics panel.
Follow-up time (months) by arm and outcome
Time to death for patients who died, and time to last contact for censored patients. Censored follow-up that is much shorter in one arm would bias a naive comparison.
| Group | n | Mean | SD | SEM | Median | Q1 – Q3 | Min – Max | Skewness | Excess kurtosis |
|---|---|---|---|---|---|---|---|---|---|
| Standard care · death | 74 | 11.16 | 9.373 | 1.09 | 9.075 | 3.202 – 15.75 | 0.1 – 42.66 | 1.13 | 1.18 |
| Standard care · censored | 26 | 19.73 | 11.09 | 2.175 | 16.3 | 10.82 – 25.81 | 6.51 – 45.96 | 0.788 | -0.229 |
| New therapy · death | 55 | 13.69 | 10.09 | 1.361 | 14.9 | 3.43 – 23.05 | 0.87 – 34.54 | 0.221 | -1.26 |
| New therapy · censored | 45 | 20.82 | 11.83 | 1.764 | 17.67 | 11.07 – 29.54 | 6.12 – 47.95 | 0.899 | -0.197 |
LabTools call
stats.describelabtools stats describe --groups @groups.json
The same method is available as an MCP tool (stats_describe) and from the desktop app's statistics panel.
Kaplan–Meier median survival
Methods paragraph
Written to go straight into a manuscript.
Median overall survival was 23.1 months with the new therapy versus 14.4 months with standard care (log-rank χ² = 9.47, 1 df, p = 0.002).
Every number on this page was computed by the LabTools statistics engine (version 0.14.3) from the example's CSV on 2026-09-23. Where a value was derived before the data reached LabTools (replicate means, paired differences, log odds ratios), the text says so. The data are simulated from a fixed random seed.
Get started
Run the same analysis on your data
Every test on this page is built into LabTools — from the statistics panel, the command line, or an AI assistant through MCP.