Willan AR, Macarthur C. Ignoring site-by-treatment effects in randomized clinical trials leads to inflated type I and II error probabilities, and what to do about it. In production 2021.

SAS file to to determine sample size for continuous outcomes




Willan AR. Accounting for treatment by center interaction in sample size determinations and the use of surrogate outcomes in the Pessary for the Prevention of Preterm Birth Trial: A simulation study. BioMed Central Trials 2016.

SAS file to generate entries in Table 1

SAS file to generate entries in Table 2




Abrahamyan L, Willan AR, Beyene J, Mclimont M, Blanchette V, Feldman BM. Using value of information methods when the disease is rare and the treatment is expensive The example of hemophilia A. Journal of General Internal Medicine 2014; 29(3):767-773.

Excel File for Example




Chen MH, Willan AR. Value of information methods for assessing a new diagnostic test. Statistics in Medicine 2014; 33(11):1801-1815.

Excel File for Example in Section 3.1 with Figure 1

Excel File for Example in Section 3.2 with Figure 2

Excel File for Example in Section 3.3 with Figure 3




Willan AR, Goereec R, Boutis K. Applying value of information methods in the evaluation of research evidence. Journal of Clinical Epidemiology 2012; 65(8): 870-876.

Excel file for VOI calculatons for ankle study

Excel file for VOI calculatons for wrist study




Willan AR, Kowgier ME. Cost-effectiveness analysis of a multinational RCT with a binary measure of effectiveness and an interacting covariate. Health Economics 2008; 17(7) :777-791.

Excel file to generate INB curves and CEAC for the CD Trial