birth {exactmaxsel}R Documentation

Birth data set by Boulesteix (2006)

Description

A data set containing 25 qualitative and quantitative variables for n=501 births in 2003 and 2004.

Usage

data(birth)

Details

The missing values are of two types: 1. Some of the variables do not concern all the births. For example, the variable Episiotomy is not relevant for cesarean births. The type NA is used for these entries. Such observations should be removed when analysing these variables. It does not make sense to imput these missing values. 2. Some questionnaires were returned incomplete, because the mother forgot some questions or did not know the answer (especially for the head circumference).

Value

A data frame with following variables

IndexMother Index of the mother (unordered)
Sex Sex of the baby (1:male,2:female)
Weight Weight of the baby in g.
Height Height of the baby in cm.
Head Head circumference of the baby in cm.
Month Month of birth (coded as 1:january,...,12:december).
Year Year of birth.
Country Country of birth (FR:France,BE:Belgium,CH:Switzerland,CA:Canada, etc).
Term Duration of the pregnancy in week.
AgeMother Age of the mother in year.
Previous Number of previous deliveries.
WeightBefore Weight of the mother before pregnancy in kg.
HeightMother Height of the mother in cm.
WeightEnd Weight of the mother at the end of the pregnancy.
Twins Twin pregnancy? (0:no,1:yes)
Intensive Number of days spent by the baby in the neonatology intensive care unit.
Cesarean Cesarean birth? (0:no,1:yes)
Planned If cesarean birth, was the cesarean planned before the beginning of labor? (0:no,1:yes)
Episiotomy If vaginal birth, did the mother have an episiotomy? (0:no,1:yes)
Tear If vaginal birth, did the mother tear? (0:no,1:yes)
Operative If vaginal birth, was it a vaginal operative birth (i.e. with forceps,vacuum extractor,etc)? (0:no,1:yes)
Induced If vaginal delivery or emergency cesarean, was the labor induced medically? (0:no,1:yes)
Membranes Did the membranes rupture before the beginning of labor? (0:no,1:yes)
Rest Was the mother prescribed bed rest for one month or more? (0:no,1:yes)
Presentation Presentation of the baby at birth (1:cephalic,2:breech,3:other,e.g. transverse).

Source

This data set was collected from internet users via french-speaking pregnancy forums in August 2004 by Anne-Laure Boulesteix.

References

A.-L. Boulesteix (2006), Maximally selected chi-square statistics for ordinal variables, Biometrical Journal 48:451-462.

Examples

# load exactmaxsel library
library(exactmaxsel)

# load data set
data(birth)

# Display the two first observations
birth[1:2,]

[Package exactmaxsel version 1.0-2 Index]