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Kaplan-Meier (tertile) plots

A Kaplan-Meier plot [Kaplan & Meier 1958 J. Amer. Statist. Assoc. 53:457] shows the survival of patient subgroups over time. For tertile-based grouping, the cohort of patients is split into three equal portions (tertiles) according to their marker expression scores. This is done separately for each marker. Where cohorts have a number of patients not exactly divisible by three, the groups will have slightly different numbers. This will also occur if more than a third of patients share the same score (as may be the case for categorical scoring).

The difference in survival between the groups is tested for significance using the log-rank (Mantel-Cox) test [Mantel 1966 Cancer Chemother. Rep. 50:163].

Available for: continuous scoring

[Top]Viewing the results

See accessing and interpreting survival analysis results.

[Top]Example output

Kaplan-Meier example based on tertile score separation

Figure 1: Example Kaplan-Meier plot based on marker score tertiles.

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