\HeaderA{bladder}{Bladder Cancer Recurrences}{bladder}
\aliasA{bladder1}{bladder}{bladder1}
\aliasA{bladder2}{bladder}{bladder2}
\keyword{datasets}{bladder}
\keyword{survival}{bladder}
\begin{Description}\relax
Data on recurrences of bladder cancer, used by many people
to demonstrate methodology for recurrent event modelling.

Bladder1 is the full data set from the study. It contains all three treatment
arms and all recurrences for 118 subjects; the maximum observed number
of recurrences is 9.

Bladder is the data set that appears most commonly in the literature. 
It uses only the 85 subjects with nonzero follow-up who were
assigned to either thiotepa or placebo.  The status variable is 1 for
recurrence and 0 for everything else (including death for any reason).
The data set is laid out in the competing risks format of the paper by
Wei, Lin, and Weissfeld.

Bladder2 uses the same subset of subjects as bladder, but formated in the
(start, stop] or Anderson-Gill style.  
Note that in transforming from the WLW to the AG style data set there
is a quite common programming mistake that leads to extra follow-up time
for 12 subjects (all those with more than 4 recurrences); this includes
some earlier releases of the data in R.
\end{Description}
\begin{Usage}
\begin{verbatim}
bladder1
bladder
bladder2
\end{verbatim}
\end{Usage}
\begin{Format}\relax
bladder1
\Tabular{ll}{
id:& Patient id\\
treatment:& Placebo, pyridoxine (vitamin B6), or thiotepa\\
number:& Initial number of tumours (8=8 or more)\\
size:& Size (cm) of largest initial tumour\\
recur:& Number of recurrences \\
start,stop:& The start and end time of each time interval\\
status:& End of interval code, 0=censored, 1=recurrence, \\
& 2=death from bladder disease, 3=death other/unknown cause\\
rtumor:& Number of tumors found at the time of a recurrence\\
rsize:& Size of largest tumor at a recurrence\\
enum:& Event number (observation number within patient)\\
}
bladder
\Tabular{ll}{
id:& Patient id\\
rx:& Treatment 1=placebo  2=thiotepa\\
number:& Initial number of tumours (8=8 or more)\\
size:& size (cm) of largest initial tumour\\
stop:& recurrence or censoring time\\
enum:& which recurrence (up to 4)\\
}
bladder2 
\Tabular{ll}{
id:& Patient id\\
rx:& Treatment 1=placebo  2=thiotepa\\
number:& Initial number of tumours (8=8 or more)\\
size:& size (cm) of largest initial tumour\\
start:& start of interval (0 or previous recurrence time)\\
stop:& recurrence or censoring time\\
enum:& which recurrence (up to 4)\\
}
\end{Format}
\begin{Source}\relax
Andrews DF, Hertzberg AM (1985), 
DATA: A Collection of Problems from Many Fields for the Student 
and Research Worker, New York: Springer-Verlag.

LJ Wei, DY Lin, L Weissfeld (1989),
Regression analysis of multivariate incomplete failure time data by
modeling marginal distributions.
\emph{Journal of the American Statistical Association},
\bold{84}.
\end{Source}

