Assessing the Impact of a Social Marketing Campaign on Program Outcomes for Users of an Internet-Based Testing Service for Sexually Transmitted and Blood-Borne Infections: Observational Study.

Developing mechanisms to track individuals from Web-based exposure to SM campaigns to outcomes of internet-based health services permits greater evaluation of the yield and cost-effectiveness of different promotional efforts. Web-based ads with high click-through rates may not have a high conversion to service use, the ultimate outcome of SM campaigns.