jointplot: Joint plot of longitudinal and survival data

In joineR: Joint Modelling of Repeated Measurements and Time-to-Event Data

Joint plot of longitudinal and survival data

Description

This function views the longitudinal profile of each unit with the last longitudinal measurement prior to event-time (censored or not) taken as the end-point, referred to as time zero. In doing so, the shape of the profile prior to event-time can be inspected. This can be done over a user-specified number of time units.

Usage

jointplot(
  object,
  Y.col,
  Cens.col,
  lag,
  split = TRUE,
  col1,
  col2,
  xlab,
  ylab,
  gp1lab,
  gp2lab,
  smooth = 2/3,
  mean.profile = FALSE,
  mcol1,
  mcol2
)

Arguments

object	an object of class jointdata.
Y.col	an element of class character identifying the longitudinal response part of the jointdata object.
Cens.col	an element of class character identifying the survival status or censoring indicator part of the jointdata object.
lag	argument which specifies how many units in time we look back through. Defaults to the maximum observation time across all units.
split	logical argument which allows the profiles of units which fail and those which are censored to be viewed in separate panels of the same graph. This is the default option. Using split = FALSE will plot all profiles overlaid on a single plot.
col1	argument to choose the colour for the profiles of the censored units.
col2	argument to choose the colour for the profiles of the failed units.
xlab	an element of class character indicating the title for the x-axis.
ylab	an element of class character indicating the title for the x-axis.
gp1lab	an element of class character for the group corresponding to a censoring indicator of zero. Typically, the censored group.
gp2lab	an element of class character for the group corresponding to a censoring indicator of one. Typically, the group experiencing the event of interest.
smooth	the smoother span. This gives the proportion of points in the plot which influence the smooth at each value. Defaults to a value of 2/3. Larger values give more smoothness. See lowess for further details.
mean.profile	draw mean profiles if TRUE. Only applies to the split = TRUE case.
mcol1	argument to choose the colour for the mean profile of the units with a censoring indicator of zero.
mcol2	argument to choose the colour for the mean profile of the units with a censoring indicator of one.

Details

The function tailors the xyplot function to produce a representation of joint data with longitudinal and survival components.

Value

A lattice plot.

Note

If more than one cause of failure is present (i.e. competing risks data), then all failures are pooled together into a single failure type.

Author(s)

Pete Philipson

References

Wulfsohn MS, Tsiatis AA. A joint model for survival and longitudinal data measured with error. Biometrics. 1997; 53(1): 330-339.

See Also

xyplot, joint, jointdata.

Examples

data(heart.valve)
heart.surv <- UniqueVariables(heart.valve, 
                              var.col = c("fuyrs", "status"),
                              id.col = "num")
heart.long <- heart.valve[, c("num", "time", "log.lvmi")]
heart.cov <- UniqueVariables(heart.valve, 
                             c("age", "sex"), 
                             id.col = "num")
heart.valve.jd <- jointdata(longitudinal = heart.long, 
                            baseline = heart.cov, 
                            survival = heart.surv,
                            id.col = "num",
                            time.col = "time")
jointplot(heart.valve.jd, Y.col = "log.lvmi", 
          Cens.col = "status", lag = 5)

joineR documentation built on Jan. 23, 2023, 5:39 p.m.