Modified Rankin Scale (mRS)

The modified Rankin Scale (mRS) is the standard global disability measure in stroke and cerebrovascular surgery. The grades are: 0, no symptoms; 1, no significant disability despite symptoms; 2, slight disability, able to look after own affairs without help; 3, moderate disability, needs some help but walks unassisted; 4, moderately severe disability, unable to walk or attend to bodily needs without help; 5, severe disability, bedridden and needing constant care; 6, death.

Studies often dichotomize the scale. mRS 0 to 2 is usually called functional independence, while some surgical series, particularly for complex aneurysms, define a good outcome as mRS 0 to 3.

Because the cut point changes what counts as success, it should always be stated alongside any reported good-outcome rate.