Overview

Hovering is one of the interactive feature for the box plots. When the user hovers the mouse cursor over a specific part of the plot, additional information related to that specific data point or summary statistic is displayed.

Hovering feature in interactive box plots contains two parts: Hover label of box and Hover label of outlier.

• Hover label of box is to display the descriptive statistics for the plots on the hovering box.

  For example: N, Mean, Median, Q1, Q3, Min and Max

• Hover label of outlier is to display the information for the outlier out of box.

  For example: Subject ID, Change from Baseline and etc.

Hover label in function prepare_boxly():

hover_var_outlier: A character vector of hover variables for outlier.

prepare_boxly <- function(meta,
                          hover_var_outlier = c("USUBJID", metalite::collect_adam_mapping(meta, analysis)$y)
                          ...
                          
)

The information for the outlier out of the box could be defined as hover_var_outlier. The developers could update hover_var_outlier to customize what to display in the hovering. The default variables selected from meta objects are “USUBJID” and the y axis variable from meta analysis plan (for boxly plot, the y axis is “CHG”). Note that the variables defined in hover_var_outlier should be one-to-one mapping to the hover_outlier_label in boxly() function which will talk about in the next section.

Hover label in function boxly():

hover_summary_var: A character vector of statistics to be displayed on hover label of box.

hover_outlier_label: A character vector of hover label for outlier.

boxly <- function(outdata,
                  hover_summary_var = c("n", "min", "q1", "median", "mean", "q3", "max"),
                  hover_outlier_label = c("Participant ID", "Parameter value"),
                  ...
                  
)

The preferred display label name in hover label of outlier corresponding to the value from meta objects could be defined as hover_outlier_label. The default label are “Participant ID” showing the “USUBJID” and the “Parameter value” showing the “CHG” (Change from Baseline). The developer could add more information (i.e., Baseline value, Analysis date). Make sure that the number of hover_outlier_label should match hover_var_outlier and the one-to-one mapping relationship between them.

The descriptive statistics displayed on hover label of box are defined as hover_summary_var. The developer could choose to display only partial descriptive statistics among “n”, “min”, “q1”, “median”, “mean”, “q3” or “max”. The default value are including all these descriptive statistics.

Example 1: Add hover label of outlier

In this example, we plan to add more hover labels for outliers.

library(boxly)

Step1: Create a list of metadata using meta_boxly(). Using Lab data as example.

meta <- meta_boxly(
  boxly_adsl,
  boxly_adlb,
  population_term = "apat",
  observation_term = "wk12",
  observation_subset = AVISITN <= 12 & !is.na(CHG)
)

Step2: Call prepare_boxly() function to prepare the metadata as required by the user. In this example, we plan to add Baseline Value and Analysis Date, so besides the default “USUBJID” and “CHG”(as y axis label collected from meta mapping object),“BASE” and “ADT” are also included in the hover_var_outlier.

outdata <- prepare_boxly(
  meta,
  hover_var_outlier = c(
    "USUBJID",
    metalite::collect_adam_mapping(meta, meta$plan$analysis)$y,
    "BASE",
    "ADT"
  )
)

Step 3: Call boxly() function to create the interactive plot. In this step, “Base Value” and “Analysis Date” are included in hover_outlier_label as displaying label for “BASE” and “ADT” which were defined in hover_var_outlier from previous step.

boxly(
  outdata,
  hover_outlier_label = c(
    "Participant ID",
    "Parameter value",
    "Base Value",
    "Analysis Date"
  )
)