Background: Despite the growing scholarly acceptance of quantitative evaluation methods, modelers still struggle to define an appropriate role for their work at the decision-making level.
Goal: To make observations about the policy relevance of mathematical and economic policy modeling in HIV and sexually transmitted disease prevention and treatment.
Results: The debate is framed within the context of the inevitability of decision making. Viewed in this light, models can inform choices between competing alternatives by leveraging existing information, integrating data from multiple sources, addressing "what if" questions, evaluating future scenarios, and providing a uniform metric for evaluation.
Conclusions: The goal of model-based evaluation should not be to supplant the decision maker, but rather to redefine the terms of the debate using quantitative methods that make the beliefs and values that lie at the heart of all difficult choices explicit.