Data are from a hypothetical study to evaluate factors associated to low birth weight. This data set contains information
on 488 births to 188 women seen in an obstetrics clinic, comprising 1 to 3 births for each woman and yielding an average of 2.6 births per women.
The outcome binary variable "low" indicates low birth weight defined as birth weight less than 2500 grams. These data are
copyrighted by John Wiley & Sons Inc. and are used here to illustrate the
calculation of prevalence ratios and corresponding confidence intervals.
Usage
data(LBW)
Arguments
Format
A data frame with 488 observations on the following 6 variables:
ID
Subject's identification.
birth
Birth order.
smoke
Smoking Status During Pregnancy (1=Yes, 0= No).
race
Race (1=White, 0= Others).
age
Age of Mother (1= age greater than 35 years, 0= age less or equal to 35 years).
low
Low Birth Weight (1 if birth weight less than 2500 grams, 0 if birth weight greater or equal to 2500 grams).
Source
The data come from
Data courtesy of University of Massachusetts Amherst
(http://www.umass.edu/statdata/statdata/stat-logistic.html) These data are copyrighted by John Wiley & Sons Inc.
We acknowledged it and use the data to illustrate the methodology included in this library.
References
Hosmer and Lemeshow (2000) Applied Logistic Regression. New York: Wiley Inter-Science. Second Edition.