ox: Measurement of oxygen saturation in blood

In MethComp: Analysis of Agreement in Method Comparison Studies

Description

61 children had their blood oxygen content measured at the Children's Hospital in Melbourne, either with a chemical method analysing gases in the blood (CO) or by a pulse oximeter measuring transcutaneously (pulse). Replicates are linked between methods; i.e. replicate 1 for each of the two methods are done at the same time. However, replicate measurements were taken in quick succession so the pairs of measurements are exchangeable within person.

Format

A data frame with 354 observations on the following 4 variables.

meth

Measurement methods, factor with levels CO, pulse

item

Id for the child

repl

Replicate of measurements. There were 3 measurements for most children, 4 had only 2 replicates with each method, one only 1

y

Oxygen saturation in percent.

Examples

data(ox)
str(ox)
ox <- Meth(ox)
with( ox, table(table(item)) )
summary( ox )
# The effect of basing LoA on means over replicates:
par( mfrow=c(1,2), mar=c(4,4,1,4) )
BA.plot(      ox , diflim=c(-20,20), axlim=c(20,100), repl.conn=TRUE )
# BA.plot( mean(ox), diflim=c(-20,20), axlim=c(20,100) )

MethComp documentation built on Jan. 20, 2020, 1:12 a.m.