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[Experimental]

Summarize results of a Poisson Negative Binomial Regression. This can be used to analyze count and/or frequency data using a linear model.

Usage

s_glm_count(
  df,
  .var,
  .df_row,
  variables,
  .ref_group,
  .in_ref_col,
  distribution,
  conf_level,
  rate_mean_method,
  weights,
  scale = 1
)

a_glm_count(
  df,
  .var,
  .df_row,
  variables,
  .ref_group,
  .in_ref_col,
  distribution,
  conf_level,
  rate_mean_method,
  weights,
  scale = 1
)

summarize_glm_count(
  lyt,
  vars,
  var_labels,
  ...,
  show_labels = "visible",
  table_names = vars,
  .stats = NULL,
  .formats = NULL,
  .labels = NULL,
  .indent_mods = NULL
)

Arguments

df

(data.frame)
data set containing all analysis variables.

.var

(string)
single variable name that is passed by rtables when requested by a statistics function.

.df_row

(data.frame)
data frame across all of the columns for the given row split.

variables

(named list of string)
list of additional analysis variables.

.ref_group

(data.frame or vector)
the data corresponding to the reference group.

.in_ref_col

(logical)
TRUE when working with the reference level, FALSE otherwise.

conf_level

(proportion)
confidence level of the interval.

lyt

(layout)
input layout where analyses will be added to.

vars

(character)
variable names for the primary analysis variable to be iterated over.

var_labels

character for label.

...

additional arguments for the lower level functions.

show_labels

label visibility: one of "default", "visible" and "hidden".

table_names

(character)
this can be customized in case that the same vars are analyzed multiple times, to avoid warnings from rtables.

.stats

(character)
statistics to select for the table.

.formats

(named character or list)
formats for the statistics.

.labels

(named character)
labels for the statistics (without indent).

.indent_mods

(named integer)
indent modifiers for the labels.

Value

A named list of 5 statistics:

n

count of complete sample size for the group.

rate

estimated event rate per follow-up time.

rate_ci

confidence level for estimated rate per follow-up time.

rate_ratio

ratio of event rates in each treatment arm to the reference arm.

rate_ratio_ci

confidence level for the rate ratio.

pval

p-value.

Functions

  • s_glm_count(): Statistics function that produces a named list of results of the investigated poisson model.

  • a_glm_count(): Formatted Analysis function which can be further customized by calling rtables::make_afun() on it. It is used as afun in rtables::analyze().

  • summarize_glm_count(): Layout creating function which can be be used for creating summary tables for analysis of count data using generalized linear models (poisson, quasipoisson).

Examples

# Internal function - s_change_from_baseline
if (FALSE) {
s_glm_count(
  df = anl %>%
    filter(ARMCD == "ARM B"),
  .df_row = anl,
  .var = "AVAL",
  .in_ref_col = TRUE,
  variables = list(arm = "ARMCD", offset = "lgTMATRSK", covariates = c("REGION1")),
  conf_level = 0.95,
  distribution = "quasipoisson",
  rate_mean_method = "ppmeans"
)
}


# Internal function - s_change_from_baseline
if (FALSE) {
a_glm_count(
  df = anl %>%
    filter(ARMCD == "ARM A"),
  .var = "AVAL",
  .df_row = anl,
  variables = list(arm = "ARMCD", offset = "lgTMATRSK", covariates = c("REGION1")),
  .ref_group = "ARM B", .in_ref_col = TRUE,
  conf_level = 0.95,
  distribution = "poisson",
  rate_mean_method = "ppmeans"
)
}

library(dplyr)
anl <- tern_ex_adtte %>% filter(PARAMCD == "TNE")
anl$AVAL_f <- as.factor(anl$AVAL)

lyt <- basic_table() %>%
  split_cols_by("ARM", ref_group = "B: Placebo") %>%
  add_colcounts() %>%
  summarize_vars(
    "AVAL_f",
    var_labels = "Number of exacerbations per patient",
    .stats = c("count_fraction"),
    .formats = c("count_fraction" = "xx (xx.xx%)"),
    .label = c("Number of exacerbations per patient")
  ) %>%
  summarize_glm_count(
    vars = "AVAL",
    variables = list(arm = "ARM", offset = "lgTMATRSK", covariates = NULL),
    conf_level = 0.95,
    distribution = "poisson",
    rate_mean_method = "emmeans",
    var_labels = "Unadjusted exacerbation rate (per year)",
    table_names = "unadj",
    .stats = c("rate"),
    .labels = c(rate = "Rate")
  ) %>%
  summarize_glm_count(
    vars = "AVAL",
    variables = list(arm = "ARM", offset = "lgTMATRSK", covariates = c("REGION1")),
    conf_level = 0.95,
    distribution = "quasipoisson",
    rate_mean_method = "ppmeans",
    var_labels = "Adjusted (QP) exacerbation rate (per year)",
    table_names = "adj",
    .stats = c("rate", "rate_ci", "rate_ratio", "rate_ratio_ci", "pval"),
    .labels = c(
      rate = "Rate", rate_ci = "Rate CI", rate_ratio = "Rate Ratio",
      rate_ratio_ci = "Rate Ratio CI", pval = "p value"
    )
  )
build_table(lyt = lyt, df = anl)
#>                                                 B: Placebo           A: Drug X        C: Combination  
#>                                                   (N=73)              (N=69)              (N=58)      
#> ——————————————————————————————————————————————————————————————————————————————————————————————————————
#> Number of exacerbations per patient                                                                   
#>   0                                             8 (10.96%)           3 (4.35%)          6 (10.34%)    
#>   1                                             9 (12.33%)          11 (15.94%)         6 (10.34%)    
#>   2                                             15 (20.55%)         18 (26.09%)         9 (15.52%)    
#>   3                                             11 (15.07%)         14 (20.29%)         15 (25.86%)   
#>   4                                             9 (12.33%)          10 (14.49%)         9 (15.52%)    
#>   5                                             9 (12.33%)          7 (10.14%)          8 (13.79%)    
#>   6                                              4 (5.48%)           4 (5.80%)           4 (6.90%)    
#>   7                                             8 (10.96%)           2 (2.90%)           0 (0.00%)    
#>   10                                             0 (0.00%)           0 (0.00%)           1 (1.72%)    
#> Unadjusted exacerbation rate (per year)                                                               
#>   Rate                                            9.1554              8.2061              7.8551      
#> Adjusted (QP) exacerbation rate (per year)                                                            
#>   Rate                                            10.2061             9.1386              7.6566      
#>   Rate CI                                    (5.6275, 18.5099)   (4.9399, 16.9060)   (4.0222, 14.5749)
#>   Rate Ratio                                                          0.8954              0.7502      
#>   Rate Ratio CI                                                  (0.3975, 2.0170)    (0.3067, 1.8348) 
#>   p value                                                             0.7897              0.5288