Ethical issues in investigation of screening strategies

Screening programs can be designed to be useful for data collection to study effectiveness of screening. High-risk populations may be identified, and screening techniques applied to a randomly selected subgroup with another subgroup serving as controls. This raises the ethical question of not applying helpful surveillance to individuals known to be at high-risk. Attention should be paid to management of controls, for example, to screen them less frequently, or at least to inform them of their increased risk and advise periodic exams. Against such recommendations is that differences between test and control groups would be minimized and the study less conclusive. Another approach is to use adaptive design, selecting the study group for a large population which is being subject to medical surveillance for some other reason. As in other clinical trails, studies of screening programs must include appropriate surveillance for controls to properly safeguard their rights and medical needs.