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ARD Poisson Test

Source: R/ard_stats_poisson_test.R
ard_stats_poisson_test.Rd

Analysis results data for exact tests of a simple null hypothesis about the rate parameter in Poisson distribution, or the comparison of two rate parameters.

Usage 

ard_stats_poisson_test(
  data,
  variables,
  na.rm = TRUE,
  by = NULL,
  conf.level = 0.95,
  ...
)

Arguments

data

(data.frame)
a data frame. See below for details.

variables

(tidy-select)
names of the event and time variables (in that order) to be used in computations. Must be of length 2.

na.rm

(scalar logical)
whether missing values should be removed before computations. Default is TRUE.

by

(tidy-select)
optional column name to compare by.

conf.level

(scalar numeric)
confidence level for confidence interval. Default is 0.95.

...

arguments passed to poisson.test().

Value

an ARD data frame of class 'card'

Details

  • For the ard_stats_poisson_test() function, the data is expected to be one row per subject.

  • If by is not specified, an exact Poisson test of the rate parameter will be performed. Otherwise, a Poisson comparison of two rate parameters will be performed on the levels of by. If by has more than 2 levels, an error will occur.

Examples 

# Exact test of rate parameter against null hypothesis
cards::ADTTE |>
  ard_stats_poisson_test(variables = c(CNSR, AVAL))
#> # An ARD data frame: 10 × 8
#>    variable context            stat_name   stat_label stat               fmt_fun
#>    <chr>    <chr>              <chr>       <chr>      <named list>       <named>
#>  1 AVAL     stats_poisson_test estimate    Estimated… 0.006052335        1      
#>  2 AVAL     stats_poisson_test statistic   Number of… 102                1      
#>  3 AVAL     stats_poisson_test p.value     p-value    9.881313e-324      1      
#>  4 AVAL     stats_poisson_test parameter   Expected … 16853              1      
#>  5 AVAL     stats_poisson_test conf.low    CI Lower … 0.004934956        1      
#>  6 AVAL     stats_poisson_test conf.high   CI Upper … 0.007347122        1      
#>  7 AVAL     stats_poisson_test method      method     Exact Poisson test <NULL> 
#>  8 AVAL     stats_poisson_test alternative alternati… two.sided          <NULL> 
#>  9 AVAL     stats_poisson_test conf.level  CI Confid… 0.95               1      
#> 10 AVAL     stats_poisson_test mu          H0 Mean    1                  1      
#> # ℹ 2 more variables: warning <named list>, error <named list>

# Comparison test of ratio of 2 rate parameters against null hypothesis
cards::ADTTE |>
  dplyr::filter(TRTA %in% c("Placebo", "Xanomeline High Dose")) |>
  ard_stats_poisson_test(by = TRTA, variables = c(CNSR, AVAL))
#> # An ARD data frame: 10 × 9
#>    group1 variable context      stat_name stat_label stat                       
#>    <chr>  <chr>    <chr>        <chr>     <chr>      <named list>               
#>  1 TRTA   AVAL     stats_poiss… estimate  Estimated… 0.7677454                  
#>  2 TRTA   AVAL     stats_poiss… statistic Number of… 57                         
#>  3 TRTA   AVAL     stats_poiss… p.value   p-value    0.2927159                  
#>  4 TRTA   AVAL     stats_poiss… parameter Expected … 61.0784                    
#>  5 TRTA   AVAL     stats_poiss… conf.low  CI Lower … 0.4655697                  
#>  6 TRTA   AVAL     stats_poiss… conf.high CI Upper … 1.305723                   
#>  7 TRTA   AVAL     stats_poiss… method    method     Comparison of Poisson rates
#>  8 TRTA   AVAL     stats_poiss… alternat… alternati… two.sided                  
#>  9 TRTA   AVAL     stats_poiss… conf.lev… CI Confid… 0.95                       
#> 10 TRTA   AVAL     stats_poiss… mu        H0 Mean    1                          
#> # ℹ 3 more variables: fmt_fun <named list>, warning <named list>,
#> #   error <named list>