Peer Review Report For: Stage 1 Registered Report:  Rationale, design and study protocol for a prospective, exploratory study Predicting Response to image-Guided Cryoneurolysis of the Greater Occipital Nerve (CryoGON) in Chronic Migraine Using a Conventional Greater Occipital Nerve Block. [version 1; peer review: 1 approved with reservations]