These data arose from a study on the efficacy of oestrogen give transdermally for treatment of severe postnatal depression. Women with major depression were randomly assigned to either a placebo control group or estrogen patch group. Prior to the treatment all women were assessed by self-ratings of depressive symptoms on the Edinburgh Postnatal Depression Scale (EPDS). The data on EPDS were collected monthly for six months once the treatment began. Higher scores on the EDPS are indicative of higher levels of depression.
A data frame with 427 rows and 5 variables:
a numeric vector giving the identifier of each woman .
a factor giving the received treatment: "placebo" or "estrogen".
a numeric vector giving the number of months since the treatment began, where -1 indicates the pretreatment assessment of the EDPS.
a numeric vector giving the value of the EDPS.
a numeric vector coded as 1 when the value of the EDPS is greater than or equal to 11 and coded as 0 in other cases.
Gregoire A.J.P., Kumar R., Everitt B., Henderson A.F. and Studd J.W.W. (1996) Transdermal oestrogen for treatment of severe postnatal depression, The Lancet 347, 930-933.
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boxplot(dep ~ visit, data=subset(depression,group=="placebo"), at=c(0:6)-0.2, col="yellow", boxwex=0.25, outline=FALSE, xaxt="n", ylab="EDPS", xlab="Months since the treatment began", ylim=range(na.omit(depression$dep))) boxplot(dep ~ visit, data=subset(depression,group=="estrogen"), add=TRUE, at=c(0:6)+0.2, col="blue", boxwex=0.25, outline=FALSE, xaxt="n") axis(1, at=0:6, labels=c(-1,1:6)) legend(-1, 8, legend=c("placebo","estrogen"), fill=c("yellow","blue"), bty="n", title="Group")
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