In a cost study, costs are measured without consideration of the intervention’s efficacy or effectiveness. There are three subtypes: (a) return on investment, (b) cost-of-illness analyses, and (c) budget impact analyses. Return-on-investment studies are generally performed to demonstrate the financial savings to a business from implementing an intervention, and results are often expressed as savings per dollar spent. These analyses often monetize the benefits of interventions. For example, a company may want to know the savings it achieved from implementing a workplace wellness program to help employees manage chronic conditions. Cost- of-illness studies are used to demonstrate the total and relative burden of a disease (e.g., the total cost of dementia). Cost-of-illness studies have also been used to demonstrate potential savings from adopting interventions. Finally, a budget impact analysis is used to determine the additional cost of implementing a new intervention from the perspective of the payer (e.g., a health plan).