snsp2mup: Two-biomarker unpaired comparison in specificity (or...

In SenSpe: Estimating Specificity at Controlled Sensitivity, or Vice Versa

Two-biomarker unpaired comparison in specificity (or sensitivity) at a controlled sensitivity (or specificity) level

Description

Point estimation and exact bootstrap-based inference

Usage

snsp2mup(mkx, n1x, mky, n1y, s0, covp=0.95, fixsens=TRUE, lbmdisx=TRUE, lbmdisy=TRUE)

Arguments

mkx	values of biomarker X, cases followed by controls.
n1x	case size of biomarker X.
mky	values of biomarker Y, cases followed by controls.
n1y	case size of biomarker Y.
s0	controlled level of sensitivity or specificity.
covp	norminal level of confidence intervals.
fixsens	fixing sensitivity if True, and specificity otherwise.
lbmdisx	larger value of biomarker X is more associated with cases if True, and controls otherwise.
lbmdisy	larger value of biomarker Y is more associated with cases if True, and controls otherwise.

Value

diff	diff[1]: difference of empirical point estimates; diff[2]: difference of oscillating bias-corrected estimates.
hvar	exact bootstrap variance estimate for diff[1].
wald_ci	wald_ci[1,]: Wald confidence interval using diff[1]; wald_ci[2,]: Wald confidence interval using diff[2].
pct_ci	percentile confidence interval.
scr_ci	scr_ci[1,]: score confidence interval using diff[1]; scr_ci[2,]: score confidence interval using diff[2].
zq_ci	extension of the BTII in Zhou and Qin (2005, Statistics in Medicine 24, pp 465–477).

Author(s)

Yijian Huang

References

Huang, Y., Parakati, I., Patil, D. H.,and Sanda, M. G. (2023). Interval estimation for operating characteristic of continuous biomarkers with controlled sensitivity or specificity, Statistica Sinica 33, 193–214.

Examples

set.seed(1234)
## simulate biomarker X with 100 cases and 100 controls
mkx <- c(rnorm(100,2,1),rnorm(100,0,1))
## simulate biomarker Y with 100 cases and 100 controls
mky <- c(rnorm(100,1,1),rnorm(100,0,1))

## compare specificity at controlled 0.95 sensitivity
est <- snsp2mup(mkx, 100, mky, 100, 0.95)

SenSpe documentation built on May 29, 2024, 9:21 a.m.