hvwi {npordtests}

Hepatic vein waveform index data

Description

This data collected by Pedersen et al. (2008) was taken from Terpstra et al. (2011). The data are calculated from doppler waveforms corresponding to 66 patients who were scheduled for a percutaneous liver needle biopsy.

Usage

data("hvwi")

Format

A data frame with 66 observations on the following 2 variables.

Group

Fibrosis groups: A:cirrhosis, B:severe, C:moderate, D:mild and E:none

Values

HVWI values for the five fibrosis groups

Source

Terpstra, J. T., Chang, C. H. and Magel, C. M. (2011). On the use of Sperman's correlation coefficient for testing ordered alternatives. Journal of Statistical Computation and Simulation, 81:11, 1381-1392.

References

Pedersen, J. F., Madsen, L. G., Vibeke, A. L. Hamberg, O., Horn, T., Federspiel, B. and Bytzer, P. (2008). A doppler waveform index to characterize hepatic vein velocity pattern and evaluate hepatic fibrosis. J. Clin. Ultrasound, 36:4, 208-211.

Examples

data(hvwi)
levels(hvwi$Group) <- c("cirrhosis", "severe", "moderate", "mild", "none")
boxplot(Values~Group,data=hvwi,xlab="Fibrosis group",ylab="HVWI value")