Building a Treeage Markov Model

Preferences/Calculation/Calculation Method/Cost Effectiveness/ Cost Payoff 1, Effectiveness Payoff
2/OK.”
15. Perform a cost-effectiveness analysis. Click on the node “Lupus,” and click “Analysis/Cost-
Effectiveness...” Select “Yes” to the question “Draw chart with cost on the vertical axis?” W ait – this could
take a few seconds. On the right-hand side, select “Text Report.” If “Text Report” is not visible, minimize
the material in the extreme right side of this panel.
Use the fourth icon of the nine icons at the upper right of this panel to save the text report as a
.pdf file. Label the file with your last name followed by 11, for example, Williams11.
Email your saved files (file 8 through file 11) to sankey@wharton.upenn.edu.
Prepare the tree for a probabilistic sensitivity analysis.
The material that follows is optional, in part because it refers to last year’s information, which
included a model that was based on TreeAge 2009. If you decide to use this material anyway, when
you’re finished, you will have a model that will allow you to do probabilistic sensitivity analyses. If
you want to do probabilistic sensitivity analyses without doing all the things described in the
following material, download “Lupus Markov Model 3” from the assignments section of
Blackboard, and go to item 21 “Conduct a probabilistic sensitivity analysis.”
16. Start by creating Dirichlet distributions for the transition probabilities and the initial distribution. For the
transition probabilities of the Active subtree in the Usual Care Markov node, click
“Values/Distributions/New/Dirichlet,” type in the box labeled Alphas list the following material
“List(66;806;56;9),” which comes from the slide below, click OK, name the distribution “ddA,” describe it as
“Dirichlet distribution of the Active subtree,” click “Close.”
Go to the Remission terminal node of the Active subtree, and click underneath the branch next to 0.07 in
the grey box. Click “Insert Distribution,” click on “ddA,” click “Use,” and make sure the material in the white
box reads “Dist(1;1).” If it doesn’t, type the material in the white box. Click “OK.” Use similar steps to label
the Active terminal node “Dist(1;2),” the Flare terminal node “Dist(1;3),” and the Death terminal node
“Dist(1:4)” (or, alternatively, leave the pound sign in place).
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