The reasonable risk-benefit ratio is one of the most significant criteria in ethical review .However , there is not a well-organized standard for risk -benefit analysis and assessment .Also the commonly used Common Rule and Duty of Personal Care Approach have their own limitations , which revoked the Component Analysis Strate-gy, unfortunately, failed again.Alex John London, as a result, tried to construct a comprehensive approach , in which he clarified reasonable riskbased on the distinction of personal interest and basic interest , as well as brought in the concept of comparator activities .Compare to the theoretical contribution of London ,A seven-step framework for risk-benefit evaluationcreated by Annette Rid and David Wendler concerns more from the practi-cal aspect .