The modified Rankin Scale (mRS) is a widely used clinical instrument to measure the degree of disability or functional dependence in the daily activities of patients who have suffered a neurological event, being particularly central in assessing outcomes after a stroke (cerebrovascular accident). It is a simple-to-apply ordinal scale that focuses on the patient's overall functional capacity rather than specific neurological deficits. The scale consists of 7 levels, ranging from 0 to 6, where each score represents a distinct level of functional outcome: 0 indicates no symptoms; 1 indicates no significant disability, despite the presence of symptoms, with the patient able to perform all usual duties and activities; 2 indicates slight disability, with the patient unable to perform all previous activities but able to look after their own affairs without assistance; 3 indicates moderate disability, where the patient requires some help but is able to walk unassisted; 4 indicates moderately severe disability, with the patient unable to walk without assistance and unable to attend to their own bodily needs without help; 5 indicates severe disability, with the patient being bedridden, often incontinent, and requiring constant nursing care and attention. Finally, the score 6 represents death. The mRS is a fundamental outcome measure in stroke clinical trials and is crucial for prognosis and therapeutic follow-up.