tp {RSurveillance}

True prevalence

Description

Estimates true prevalence and confidence limits for given sample size and result, according to specified method

Usage

tp(x, n, se, sp, type = "blaker", conf = 0.95)

Arguments

x

number of positive units (scalar)

n

sample size (no. units sampled) (scalar)

se

test sensitivity (scalar)

sp

test specificity (scalar)

type

method for estimating CI, one of c("normal", "c-p", "sterne", "blaker", "wilson", "all")

conf

desired level of confidence for CI, default = 0.95 (scalar)

Value

list with 2 elements, a matrix of apparent prevalence and lower and upper confidence limits and a matrix of true prevalence and lower and upper confidence limits using the chosen method(s)

Examples

# examples for tp
x<- 20
n<- 120
se<- 0.9
sp<- 0.99
conf<- 0.95
tp(x, n, se, sp, "all")
tp(x, n, se, sp, "c-p")
tp(x, n, 0.95, 0.9, "c-p")