tlm (version 0.2.0)

cotinine: Birth Weight and Cord Serum Cotinine

Description

Simulated data for birth weight and cord serum cotinine levels in 351 newborns.

Usage

cotinine

Format

A data.frame with 351 observations on the following 4 variables:

cotinine

cord serum cotinine level in the mother (ng/ml).

logcotinine

logarithm of cotinine.

weight

birth weight (g).

underweight

a factor with levels no and yes, indicating underweight (weight < 2500 g).

Details

Data were simulated to emulate true data pattern observed in a real study (see References).

References

Pichini S et al. Cord serum cotinine as a biomarker of fetal exposure to cigarette smoke at the end of pregnancy. Environmental Health Perspectives. 2000;108(11):1079-1083.

Examples

data(cotinine)
par(las = 1, mfrow = c(2, 2))
with(cotinine, plot(cotinine, weight))
with(cotinine, plot(logcotinine, weight))
with(cotinine, boxplot(cotinine ~ underweight))
with(cotinine, boxplot(logcotinine ~ underweight))