Dynamic modeling in medical technology assessment. Fitting hearing aids in The Netherlands

The main objective of this article is to demonstrate the usefulness of dynamic modeling for an economic assessment of technology in health care. Specifically, this approach is applied to assess the impact of the use of hearing aids in Dutch health care.

The population is divided into different health classes between which, over time, transitions occur. Transition probabilities are derived from exogenous data. The transitions are associated with economic and societal costs and benefits. People who are satisfied with their hearing aids experience benefits. These benefits are expressed by quality-adjusted life-years (QALYs). Costs are made during transitions (mainly the fitting of hearing aids). A cohort analysis is carried out, starting with people in a particular age group. The starting point is a fixed number of people within this age group, who are followed during their whole lifetime.

Costs per QALY ratios are calculated for two health programs. The Fitting Hearing Aid Program describes the present situation in the Netherlands; the Post-purchase Counseling Hearing Aid Program is a hypothetical addition to the first program, where an intervention based on a Dutch study is undertaken to improve satisfaction with hearing aids. Future benefits and costs are discounted at a rate of 5%.

The dynamic modeling approach provides a more realistic picture than a static approach. Particularly, the cost-effectiveness of the Fitting Hearing Aid Program is compared with the Post-purchase Counseling Hearing Aid Program.