OBSOLETE: Replaced by Oct. 25, 2017 New guidanceFDA CDRH Guidance for Industry “Deciding when to submit a 510(k) for a change to existing device” issued January 10, 1997. This provides guidance on determining whether a change to previously cleared device requires submission of a 510(k). This guidance provides a series of questions and flowcharts with explanations of things to be considered. Question B8 Identifies software and firmware changes and question B4 identifies changes to the ergonomics of the patient/user interface. If such changes occur then a series of four additional questions need to be answered to determine if the 510(k) is required.