Cost-minimization studies are a special type of cost-effectiveness analysis where the competing treatments have equivalent outcomes. In other words, cost-minimization analysis is appropriate when the effectiveness of competing treatments is equal. In this situation, the preferred treatment is that which has the lower cost. One example of this is the comparison of two behavioral programs for depression that result in equivalent reduction in depressive symptoms.
Finally, a cost-benefit analysis evaluates both costs and effectiveness in monetary terms. This approach is not as popular as cost-effectiveness analysis or related types (cost-utility analysis and cost-minimization analysis). This is due primarily to the challenges of attaching a monetary value to effectiveness measures. Effectiveness can be difficult to value in monetary terms because there may be nonmarketed benefits to behavioral interventions; thus the true value of health or a behavioral change may be difficult to elucidate. However, theoretically, a cost-benefit analysis has several advantages. Converting benefits into monetary terms helps to aggregate outcomes from multidimensional interventions. However, aggregation of outcomes is also accomplished in a cost-utility analysis. More importantly, a cost-benefit analysis eliminates the need for determining what constitutes being cost-effective. In a cost-benefit analysis, the decision rule is simply benefits — costs. If benefits — costs > $0, then the intervention generates net financial benefits—in other words, a net savings—and should be implemented. On the other hand, if the benefits — costs
< $0, then the intervention results in net costs. In this case, rejection of the intervention may be warranted, if costs are the main factor determining its adoption. The intervention may be adopted despite its net costs if there are other factors in its favor (e.g., improved participant satisfaction or adherence compared to treatment alternatives).