I believe SOPs are required for the research phase, because there should be steps on the thought process of you reaching that idea, exploring the different possibilities, creating different designs, as well as other things. The DHF includes files from the devices inception, and with good documentation practices in lies proper SOPs to document all aspects. The main purpose of SOPs is for there to be organization and checks and balances for everything that is done with the medical device. We are dealing with instruments that may be life or death in certain circumstances for humans, so it is important to have a proper process in place even in the research aspect.