*! version 1.0.4 21apr2015

help stjmgraph also see: stjm, stjm postestimation

Title

stjmgraph -- Joint longitudinal and survival graph

Syntax

stjmgraph long_depvar [if] [in] [, options]

panel(varname) panel identification variable

indcensgraphopts(string) options to pass to each individual line plot for censored observations

indeventgraphopts(string) options to pass to each individual line plot for observations with the event

censgraphopts(string) options to pass to the overall twoway plot for censored observations

eventgraphopts(string) options to pass to the twoway plot for observations with the event

combineopts(string) options to pass to the final graph combine

draw displays all graphs used to create the final combined graph

lowess overlay a lowess smoother

adjust adjust the timescale by scaling to event/censoring time

nodata suppresses displaying individual trajectories for every patient

Description

stjmgraph creates a longitudinal trajectory plot, whereby the timescale can be adjusted by taking away each patient's
event/censoring time. This form of graph can be useful to display joint longitudinal and survival data, giving an indication
of any association between the two processes. A separate plot is created for patients who were censored and for patients who
experienced the event of interest. They are then combined using graph combine.

The dataset must be stset correctly into enter and exit times, using the enter option; see [ST] stset.
stjmgraph uses _t0 to denote measurement times. For example, below we have 3 patients with 2, 5 and 3 measurements
each, respectively.

id _t0 _t _d long_resp

1 0 0.2 0 0.93
1 0.2 0.7 0 1.32
2 0 0.5 0 1.15
2 0.5 1.2 0 1.67
2 1.2 1.6 0 1.92
2 1.6 1.9 0 2.65
2 1.9 2.6 1 3.15
3 0 2 0 0.25
3 2 2.3 0 0.21
3 2.3 2.4 1 0.31

See stjm for more details.

Options

panel(varname) defines the panel identification variable.

indcensgraphopts(string) pass options to each individual line graph of censored observations. See twoway_options.

indeventgraphopts(string) pass options to each individual line graph of observations who experienced the event of interest. See twoway_options.

censgraphopts(string) pass options to the twoway graph of censored observations. See twoway_options.

eventgraphopts(string) pass options to the twoway graph of observations who experienced the event of interest. See twoway_options.

combineopts(string) pass options to the final graph combine. See graph combine.

draw displays the intermediate twoway plots used to create the final graph.

lowess overlays a lowess smoother to aid interpretation.

adjust scales the timescale (x-axis) by taking away each patient's censoring/event time from their measurement times. This is useful to see differences in trajectories
prior to an event.

nodata suppresses the display of individual trajectories for each patient.

Example

Load primary biliary cirrhosis dataset:

. use http://fmwww.bc.edu/repec/bocode/s/stjm_pbc_example_data

stset the data:

. stset stop, enter(start) f(event=1) id(id)

Create joint plot:

. stjmgraph logb, panel(id) lowess adjust

Author

Michael J. Crowther

University of Leicester

UK

E-mail: michael.crowther@le.ac.uk.

Please report any errors you may find.

References

Crowther MJ, Abrams KR and Lambert PC (2012). Joint modelling of longitudinal and survival data. (Submitted).

Also see

Online: stjm, stjm postestimation