Number-at-risk builders for the TTE grammar

Builder functions for the risktable layer (er_tte_add_risktable()), drawing a row of risk counts per stratum at a grid of time points. Unlike every other TTE-grammar builder, this one's geoms are drawn into their own patchwork panel below the curve, not onto the curve's panel directly – see er_tte_build().

Usage

er_style_tte_risktable_text(
  data,
  config,
  stratify,
  time,
  strata,
  theme,
  text_size = 3.5,
  show_percent = FALSE,
  ...
)

Arguments

data

The original data frame (object$data).

config

Configuration for the risktable layer (populated by er_tte_add_risktable()): config$table (time/n_risk/strata/ n_baseline – the stratum's time-zero number at risk, used by show_percent below – one row per requested time break per stratum) and config$breaks (the time breaks themselves, also used as the curve panel's x-axis ticks).

stratify

Logical: whether the fit is stratified (!is.null(object$strata)).

time

object$time (name/label/limits).

strata

object$strata (var/label), or NULL when unstratified.

theme

object$theme.

text_size

Size of the risk-count text. Default 3.5.

show_percent

Whether to append each break's n_risk as a percentage of that stratum's own baseline (time-zero) size, formatted via er_tte_theme()'s format_percent. Default FALSE (a bare count, the previous behaviour).

...

Additional named arguments forwarded from er_tte_add_risktable()'s own ....

Value

A geom, or a list of geoms.

Details

See er_style_tte() for the shared interface every TTE-grammar builder implements.

Rows are ordered top-to-bottom in the same order strata first appear in config$table (reversed, since a ggplot2 discrete y-axis plots its first level at the bottom); an unstratified fit gets a single "All" row.

show_percent = TRUE displays "<n_risk> (<percent>%)" instead of a bare n_risk, using er_tte_theme()'s format_percent (defaulting to scales::label_percent(accuracy = 1)) to format n_risk / n_baseline – see config above for where n_baseline comes from.

er_style_tte_risktable_text() is tagged er_style_tag(fn, layer = "risktable"), so er_tte_add_risktable() errors informatively if handed a builder tagged for a different layer.

See also

er_tte_add_risktable(), er_style_tte()

Examples

library(survival)
lung |>
  er_tte(time, status == 2) |>
  er_tte_add_curve() |>
  er_tte_add_risktable(style = er_style_tte_risktable_text, text_size = 4) |>
  plot()