This helper, to be used with `tbl_custom_summary()`

, creates a function
computing a proportion and its confidence interval.

```
proportion_summary(
variable,
value,
weights = NULL,
na.rm = TRUE,
conf.level = 0.95,
method = c("wilson", "wilson.no.correct", "exact", "asymptotic")
)
```

- variable
String indicating the name of the variable from which the proportion will be computed.

- value
Value (or list of values) of

`variable`

to be taken into account in the numerator.- weights
Optional string indicating the name of a weighting variable. If

`NULL`

, all observations will be assumed to have a weight equal to`1`

.- na.rm
Should missing values be removed before computing the proportion? (default is

`TRUE`

)- conf.level
Confidence level for the returned confidence interval. Must be strictly greater than 0 and less than 1. Default to 0.95, which corresponds to a 95 percent confidence interval.

- method
Confidence interval method. Must be one of

`c("wilson", "wilson.no.correct", "exact", "asymptotic")`

. See details below.

Computed statistics:

`{n}`

numerator, (weighted) number of observations equal to`values`

`{N}`

denominator, (weighted) number of observations`{prop}`

proportion, i.e.`n/N`

`{conf.low}`

lower confidence interval`{conf.high}`

upper confidence interval

Methods `c("wilson", "wilson.no.correct")`

are calculated with
`stats::prop.test()`

(with `correct = c(TRUE, FALSE)`

). The default method,
`"wilson"`

, includes the Yates continuity correction.
Methods `c("exact", "asymptotic")`

are calculated with `Hmisc::binconf()`

and the corresponding method.

Example 1

Other tbl_custom_summary tools:
`add_overall()`

,
`continuous_summary()`

,
`ratio_summary()`

,
`tbl_custom_summary()`

```
# Example 1 ----------------------------------
proportion_summary_ex1 <-
Titanic %>%
as.data.frame() %>%
tbl_custom_summary(
include = c("Age", "Class"),
by = "Sex",
stat_fns = ~ proportion_summary("Survived", "Yes", weights = "Freq"),
statistic = ~"{prop}% ({n}/{N}) [{conf.low}-{conf.high}]",
digits = ~ list(
function(x) {
style_percent(x, digits = 1)
},
0, 0, style_percent, style_percent
),
overall_row = TRUE,
overall_row_last = TRUE
) %>%
bold_labels() %>%
modify_footnote(
update = all_stat_cols() ~ "Proportion (%) of survivors (n/N) [95% CI]"
)
```