birthwt.grpreg {grpreg} | R Documentation |
Risk Factors Associated with Low Infant Birth Weight
Description
The birthwt.grpreg
data frame has 189 rows and 18 columns.
The data were collected at Baystate Medical Center, Springfield, Mass
during 1986. This data frame is a reparameterization of the
birthwt
data frame from the MASS
package.
Usage
data(birthwt.grpreg)
Format
This data frame contains the following columns:
- low
- indicator of birth weight less than 2.5kg
- bwt
- birth weight in kilograms
- age1,age2,age3
- Orthogonal polynomials of
first, second, and third degree representing mother's age in years
- lwt1,lwt2,lwt3
- Orthogonal polynomials of
first, second, and third degree representing mother's weight in pounds
at last menstrual period
- white,black
- Indicator functions for mother's race;
"other" is reference group
- smoke
- smoking status during pregnancy
- ptl1,ptl2m
- Indicator functions for one or for two or
more previous premature labors, respectively. No previous premature
labors is the reference category.
- ht
- history of hypertension
- ui
- presence of uterine irritability
- ftv1,ftv2,ftv3m
- Indicator functions for
one, for two, or for three or more physician visits during the first
trimester, respectively. No visits is the reference category.
Source
MASS
. R
package. Available at http://cran.r-project.org
.
References
Venables, W. N. and Ripley, B. D. (2002) Modern Applied
Statistics with S. Fourth edition. Springer.
Hosmer, D.W. and Lemeshow, S. (1989) Applied Logistic
Regression. New York: Wiley
[Package
grpreg version 1.0
Index]