The Low Birthweight data

Description

A subset of the data collected in the Auckland Birthweight Collaborative (ABC) Study.

Usage

data(lowbirth.bin)

Format

A data frame with 1148 observations on the following 18 variables.

sgagp

A factor defining the case (sga) and control (aga) status of the baby.

sex

1=female or 2=male

instudy

A factor with levels retro and strata, used as the obstype variable in function call

htstrat

A factor with levels as class intervals of mother's height

ethnicdb

A factor with levels A (Asian), E (Euro.), M (Maori) or P (Pacifican)

mstrat

Marital status of the mother

occ

Mother's ccupational group, 1 to 3 (3 is highest)

mumht

Height of the mother in cm

mumwt

Weight of the mother in kg

bmi

Body mass index of the mother

smoke

Smoking status of the mother prior to pregnancy

smokedb

Smoking variable from database

age1st

Mother's age at first pregnancy

hyper

Any hypertension (1=yes, 0=no)

edstratdb

Mother's educational level

eductrm

Mother's age left school

mstratdb

As for mstrat with some levels combined

counts

Number of subjects with each observation (frequency)

Details

The ABC study was conducted in 1995-1997 in order to find potential risk factors associated with small-for-gestational-age babies in New Zealand. It was a population-based case-control study with the cases being those babies with their birthweights equal to or below the sex-specific 10th percentile for gestational age in the population.

The lowbirh.bin is a semi-random subset of the original data.

References

Description of the missreg Library, Wild and Jiang, 2007.