Discrete Event Simulation for Health Technology Assessment

263Validation

the pieces are built but must be repeated as interacting blocks are incorpo-

rated. Itis best if the testing is done by someone different than the person

constructing the model. Developers of software have elaborated detailed

approaches to completing this kind of verication, and there is an exten-

sive literature on the subject (Beyer 2014). The following sections address

common aspects of DES for HTA that should be checked as part of the

verication process.

The whole verication procedure should be carefully documented, includ-

ing what was tested, by whom, how it was tested, when, and what were the

results of the testing. In practical terms, an external assessor addressing this

aspect, after the model is completed, can only rel ...