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Kaplan-Meier risk table

Source: R/km_risk_table.R
km_risk_table.Rd

Tabulate the number at risk at selected follow-up times.

Usage

km_risk_table(
  data,
  time,
  event,
  by = NULL,
  times,
  digits = 1,
  extend = TRUE,
  format = c("flextable", "gt", "tibble"),
  theme = c("minimal")
)

Arguments

data

A data.frame containing survival time and event status.

time

Survival follow-up time. Quoted and bare names are accepted.

event

Event indicator. Quoted and bare names are accepted. Numeric 0/1, numeric 1/2, logical, character, and factor variables are accepted. For two-level character or factor variables, the second level is treated as the event.

by

Optional grouping variable for separate Kaplan-Meier risk tables. Quoted and bare names are accepted.

times

Numeric vector of follow-up times for the risk table.

digits

Number of digits for displayed follow-up times.

extend

Logical. If TRUE, requested times beyond the observed follow-up range are retained using the last available Kaplan-Meier risk set.

format

Output format. One of "flextable" (default), "gt", or "tibble".

theme

Table styling preset.

Value

A list of class c("gtregression","km_risk_table", ...) with elements:

table

A flextable, gt_tbl, or NULL when format = "tibble".

table_body

Tibble with Kaplan-Meier risk table counts.

table_display

Display data frame used to render the table.

fit

Fitted survfit object.

time,event,by,times,format,source

Metadata fields.

Details

The At risk column gives the number still under observation at each requested time. The Events and Censored columns are interval counts up to each requested time point as returned by summary.survfit().

Examples

lung_data <- data_lungcancer
lung_data$trt <- factor(lung_data$trt, levels = c(1, 2),
                        labels = c("Standard", "Test"))

km_risk_table(
  data = lung_data,
  time = time,
  event = status,
  by = trt,
  times = c(0, 90, 180, 365)
)

km_risk_table(
  data = lung_data,
  time = "time",
  event = "status",
  times = c(0, 90, 180),
  format = tibble
)
#> # A tibble: 3 × 5
#>   Group    Time N.risk Events Censored
#>   <chr>   <dbl>  <dbl>  <dbl>    <dbl>
#> 1 Overall     0    137      0        0
#> 2 Overall    90     62     73        3
#> 3 Overall   180     27     30        4