Converts between etm and msdata format
Converts multi-state data back and forth between etm and msdata formats. Covariates have to be dealt with separately.
etm2msdata(etmdata, id, tra, covs)
etmdata |
Multi-state data in |
id |
Column name identifying the subject id |
tra |
Transition matrix in |
covs |
Vector of column names containing covariates to be included |
msdata2etm will convert from msdata format to etm
format; etm2msdata will convert from etm format to
msdata format. Both msdata2etm and etm2msdata work with
basic time-fixed covariates. Time-dependent covariates are not supported.
The function msdata2etm will work for transition-specific covariates,
but the result does not really make much sense when used in etm.
Hein Putter H.Putter@lumc.nl
# Transition matrix for illness-death model
tmat <- trans.illdeath()
# Data in wide format, for transition 1 this is dataset E1 of
# Therneau & Grambsch (T&G)
tg <- data.frame(id=1:6,illt=c(1,1,6,6,8,9),ills=c(1,0,1,1,0,1),
dt=c(5,1,9,7,8,12),ds=c(1,1,1,1,1,1),
x1=c(1,1,1,0,0,0),x2=c(6:1))
# Data in long format using msprep
tglong <- msprep(time=c(NA,"illt","dt"),status=c(NA,"ills","ds"),
data=tg,keep=c("x1","x2"),trans=tmat, id="id")
# Same thing in etm format
tra <- trans2tra(tmat)
tgetm <- msdata2etm(tglong, id="id")
tgetm <- msdata2etm(tglong, id="id", covs=c("x1", "x2")) # with covariates
# And back
etm2msdata(tgetm, id="id", tra=tra)
etm2msdata(tgetm, id="id", tra=tra, covs=c("x1", "x2")) # with covariatesPlease choose more modern alternatives, such as Google Chrome or Mozilla Firefox.