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Split Function to Configure Risk Difference Column

Source: R/riskdiff.R
add_riskdiff.Rd

[Stable]

Wrapper function for rtables::add_combo_levels() which configures settings for the risk difference column to be added to an rtables object. To add a risk difference column to a table, this function should be used as split_fun in calls to rtables::split_cols_by(), followed by setting argument riskdiff to TRUE in all following analyze function calls.

Usage 

add_riskdiff(
  arm_x,
  arm_y,
  col_label = "Risk Difference (%) (95% CI)",
  pct = TRUE
)

Arguments

arm_x

(character)
Name of reference arm to use in risk difference calculations.

arm_y

(character)
Name of arm to compare to reference arm in risk difference calculations.

col_label

(character)
Label to use when rendering the risk difference column within the table.

pct

(flag)
whether output should be returned as percentages. Defaults to TRUE.

Value

A closure suitable for use as a split function (split_fun) within rtables::split_cols_by()

when creating a table layout.

See also

stat_propdiff_ci() for details on risk difference calculation.

Examples 

adae <- tern_ex_adae
adae$AESEV <- factor(adae$AESEV)

lyt <- basic_table() %>%
  split_cols_by("ARMCD", split_fun = add_riskdiff(arm_x = "ARM A", arm_y = "ARM B")) %>%
  count_occurrences_by_grade(
    var = "AESEV",
    riskdiff = TRUE
  )

tbl <- build_table(lyt, df = adae)
tbl
#>              ARM A        ARM B        ARM C      Risk Difference (%) (95% CI)
#> ——————————————————————————————————————————————————————————————————————————————
#> MILD        6 (3.0%)     4 (2.3%)     2 (1.2%)          0.7 (-2.5 - 3.9)      
#> MODERATE   19 (9.4%)    15 (8.5%)    14 (8.6%)          0.9 (-4.8 - 6.7)      
#> SEVERE     34 (16.8%)   38 (21.5%)   32 (19.8%)        -4.6 (-12.6 - 3.3)