prec_sens | R Documentation |
Because sensitivity (true positives/total number of positives) and specificity (true
negatives/total number of negatives) are simple proportions, these
functions act as wrappers for prec_prop
.
prec_sens( sens, n = NULL, ntot = NULL, prev = NULL, conf.width = NULL, round = "ceiling", ... ) prec_spec( spec, n = NULL, ntot = NULL, prev = NULL, conf.width = NULL, round = "ceiling", ... )
sens, spec |
proportions. |
n |
number of observations. |
ntot |
total sample size. |
prev |
prevalence of cases/disease (i.e. proportion of |
conf.width |
precision (the full width of the confidence interval). |
round |
string, round calculated |
... |
options passed to prec_prop (e.g. method, conf.width, conf.level). |
If ntot
and prev
are given, they are used to calculate
n
.
Object of class "presize", a list of arguments (including the computed one) augmented with method and note elements.
Calculated n
can take on non-integer numbers, but
prec_prop
requires integers, so the calculated n
is rounded
according to the approach indicated in round
.
prec_prop
# confidence interval width with n prec_sens(.6, 50) # confidence interval width with ntot and prevalence (assuming 50% prev) prec_sens(.6, ntot = 100, prev = .5) # sample size with confidence interval width prec_sens(.6, conf.width = 0.262)
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.