# Customizing Plot Limits for AE Proportions and Differences

    library(forestly)
    library(metalite)

The interactive AE forest plots include AE-specific tables. In this vignette, we demonstrate how users can customize the limits when plotting AE proportions, their differences, and corresponding confidence intervals.

# 1 Step 1: build your metadata

Building interactive AE forest plots starts with constructing the metadata. The detailed procedure for building metadata is covered in the vignette Generate Interactive AE Forest Plots with Drill Down to AE Listing. Therefore, in this vignette, we will skip those details and directly use the metadata created there.

    adsl <- forestly_adsl
    adae <- forestly_adae

    adsl$TRTA <- factor(forestly_adsl$TRT01A,
      levels = c("Xanomeline Low Dose", "Placebo"),
      labels = c("Low Dose", "Placebo")
    )
    adae$TRTA <- factor(forestly_adae$TRTA,
      levels = c("Xanomeline Low Dose", "Placebo"),
      labels = c("Low Dose", "Placebo")
    )

    meta <- meta_adam(population = adsl, observation = adae) |>
      define_plan(plan = plan(
        analysis = "ae_forestly",
        population = "apat",
        observation = "apat",
        parameter = "any;drug-related"
      )) |>
      define_analysis(name = "ae_forestly", label = "Interactive Forest Plot") |>
      define_population(
        name = "apat", group = "TRTA", id = "USUBJID",
        subset = SAFFL == "Y", label = "All Patient as Treated"
      ) |>
      define_observation(
        name = "apat", group = "TRTA",
        subset = SAFFL == "Y", label = "All Patient as Treated"
      ) |>
      define_parameter(
        name = "any",
        subset = NULL,
        label = "Any AEs",
        var = "AEDECOD", soc = "AEBODSYS"
      ) |>
      define_parameter(
        name = "drug-related",
        subset = toupper(AREL) == "RELATED",
        label = "Drug-related AEs",
        var = "AEDECOD", soc = "AEBODSYS"
      ) |>
      meta_build()

# 2 Step 2: customize limits for AE proportion/difference plotting

Users can control these limits by specifying the `prop_range = ...` and `diff_range = ...` arguments within the `format_ae_forestly()` function. Specifically, `prop_range` sets the limits for AE proportions, while `diff_range` defines the limits for AE proportion differences and their confidence intervals.

By default, the limits are set based on the minimum and maximum values observed across all AEs, rounded and extended by ±2 units for better visualization.

In the example below, we modify the AE proportion limits to range from -0.5 to 30, and the AE proportion difference limits from -10 to 35. Please note that if the specified range does not fully encompass the observed minimum or maximum values, a warning message will be displayed.

    meta |>
      prepare_ae_forestly() |>
      format_ae_forestly(prop_range = c(-0.5, 30), diff_range = c(-10, 35)) |>
      ae_forestly()

AE Criteria
Incidence (%) in One or More Treatment Groups