The researcher in charge of confirming inclusion and exclusion criteria, fulfilling the Basic Data Formulary and providing the patient with the Informed Consent Format, will not be aware of the allocation sequence order until these 3 documents have been applied to the participant and a consecutive number has been generated according to their order of inclusion in the trial. After that, a member of the research team in the prism storehouse will verify the existence of a prism pair marked with the same number as the consecutive number assigned to the patient, and only in that point allocation status of the participant will be known.