This guidance document describes the Food and Drug Administration's (FDA or Agency) current approach to considering uncertainty in making benefit-risk determinations to support FDA premarket decisions for medical device premarket approval applications (PMAs), De Novo requests, and humanitarian device exemption (HDE) applications. FDA believes the approach described in this guidance promotes the public health by helping patients have timely access to new medical devices meeting the applicable statutory standard for safety and effectiveness, such that probable benefits of device use outweigh the probable risks and the device will provide clinically significant results in a significant portion of the target population, based on the totality of the valid scientific evidence.