Cotinine: Salivary Cotinine Measurements on Scottish Schoolchildren.

In R4HCR: R for Health Care Research

Salivary Cotinine Measurements on Scottish Schoolchildren.

Description

Duplicate salivary cotinine measurements for 20 Scottish schoolchildren.

Usage

Cotinine

Format

A data frame with 20 observations on the following 3 variables.

subject

Subject identifier

cotinine1

First of two cotinine measurements (ng/ml).

cotinine2

Second of two cotinine measurements (ng/ml).

Source

Cited as originating from D Strachan (by personal communication), first printed in Bland and Altman (1996).

References

Bland, J.M. and Altman, D.G., 1996. Measurement error proportional to the mean. BMJ: British Medical Journal, 313(7049), p.106.

Examples

data(Cotinine, package = "R4HCR")

mean <- rowMeans(Cotinine[,c(2,3)])

range <- abs(Cotinine[,2] - Cotinine[,3])

# error vs the mean.
plot(mean,range, pch=16, xlab = "Average of first and second measurement")

R4HCR documentation built on Sept. 30, 2024, 9:46 a.m.