As far as my understanding, Guidance documents are not mandatory but it a template for reading directives. Guidance documents in EU, I would rank NB-MED higher than any other because it is written by the notified bodies which is the key component of the EU and it has the authority to inspect the devices and their findings carry a weight on passing or failing of a device. So to me, this carries the most weight. And component authorities accept their judgement and these component authorities write the MEDDEV Documents. Thus, I would look at NB-MED before anything else. As I do not have actual experience working with such conditions, my answer is based on what Dr. Simon mentioned in the notes and my understanding of the system in EU.