Please answer the following questions after carefully reading the paper: P. Falcoz, C. Binquet, F. Clement, D. Kaili, C. Quantin, S. Chocron and J. Etievent (2003) “Management of the second episode of spontaneous Pneumothorax: a decision analysis,” Annals of Thoracic Surgery, Vol. 76, pp. 1843–8

a) What kind of model was developed? What was the aim(s) of the model?

b) Briefly describe the possible decision alternatives and outcomes.

c) Using a suitable package such as Precision Tree, draw, for this problem, a decision tree such as the one in Figure 1, including all parameters (baseline values)

d) Determine the expected cost and effectiveness of each decision alternative. Use the tree drawn in c) and show all working. Compare your results with those in Table 2.

e) Study

• The effect of mean length for Conservative Management (CM) on expected cost

• The two-way effects of mean length of stay for CM and VATS on expected cost Comment on your results, in particular on:

- how they compare with those in the paper

- the use of sensitivity analysis in decision analysis.