|Cost-Effectiveness Tool for Evaluating Interventions to Prevent Mother-to-Child Transmission - Manual and Model (UNAIDS, 2000, 94 p.)|
This is the rate at which future financial costs and health benefits are reduced when converted to their equivalent value in the present. This adjustment is made to reflect the greater societal preference for money and health benefits in the present compared with the same quantum of money or health benefits at a future date. The rate of 3% is a well-accepted rate for developing countries and is recommended by the World Bank. Changing the discount rate can have a large effect on health outcome as measured in DALYs. We therefore recommend that you not alter this value unless you have a strong rationale for doing so.
Influence on cost-effectiveness: High. The choice of discount rate can have a strong effect on the economic appraisal of MTCT programs. For example, 50 life-years discounted at 3% are equivalent to 25.7 net present life years. At a 5% discount rate, those same 50 years have a net present value of only 18.3 life-years, a decrease of 1/3.
Expected effort of data collection: Low. Although the choice of discount rate can be important, it is difficult to select the objectively correct rate in a given situation. For ease of comparison with other studies, we recommend that you use the 3% default.
C44. Discount rate. The default value is 3%. You may enter a different value here. Numbers below 0% or above 15% compute but yield an error message in the adjacent cell (D44) since values outside the range are likely to be in error. Data Sources: See Appendix B in the World Banks 1993 World Development Report for an explanation of the recommended 3% discount rate.