Modified Rankin Scale (MRS)

Purpose of the measure

The Modified Rankin Scale (MRS) is a single item, global outcomes rating scale for patients post-stroke. It is used to categorize level of functional independence with reference to pre-stroke activities rather than on observed performance of a specific task.

Available versions

The original Rankin Scale was developed in Scotland in 1957 and was used to assess disability in patients with acute stroke (Rankin, 1957). It consisted of a single item, with five grades representing no, slight, moderate, moderately severe, and severe disability. The Rankin Scale was modified in 1988 as part of a study of aspirin in stroke prevention (UK-TIA Study Group, 1988) and renamed the MRS. This modification was not reported in the aspirin study, but was described subsequently by van Swieten, Koudstaal, Visser, Schouten, and van Gijn (1988). An additional grade was included (grade 0 = no symptoms at all) because of reported concerns about a lack of grading comprehensiveness. The wording of the definitions for grades 1 and 2 were also altered because of concerns of ambiguity (Bamford, Sandercock, Warlow, & Slattery, 1989). The changes were reportedly also made to accommodate language disorders and cognitive defects, to allow comparison between patients with different kinds of neurological deficits and to add a further dimension by referring to previous activities (van Swieten et al., 1988).

Features of the measure

Items:
The MRS is a single item scale.

The conventional method of administration for the MRS is a guided interview process. The assessment is carried out by asking the patient about their activities of daily living, including outdoor activities. Information about the patient’s neurological deficits on examination, including aphasia and intellectual deficits, should be obtained. All aspects of the patient’s physical, mental performance, and speech should be combined in the choice of a single MRS grade.

The categories within the MRS have been criticized as being broad and poorly defined, left open to the interpretation of the individual rater (Wilson et al., 2002). A structured interview format for the administration of the MRS is available (see section Alternative forms of the Modified Rankin Scale – MRS).

Scoring:
A single MRS grade should be assigned based on the following criteria (Dromerick, Edwards, & Diringer, 2003):

Rankin Grade Description
0 No symptoms
1 No significant disability despite symptoms; able to carry out all usual duties and activities
2 Slight disability: unable to carry out all previous activities but able to look after own affairs without assistance
3 Moderate disability: requiring some help, but *able to walk without assistance
4 Moderately severe disability: unable to walk without assistance, and unable to attend to own bodily needs without assistance
5 Severe disability: bedridden, incontinent, and requiring constant nursing care and attention

* It is unclear whether the term ‘without assistance’ allows for aids or modifications, or whether it refers only to assistance from another person.

Some studies have examined the ability of MRS scores to be dichotomized. de Haan, Limburg, Bossuyt, van der Meulen, and Aaronson (1995) suggested that MRS scores be dichotomized for the purposes of comparison in evaluating the effectiveness of an intervention. They suggested that a score of 0-3 indicate mild to moderate disability, and a score of 4-5 indicate severe disability. Currently, there is no standardized or consistent method of dichotomization (Sulter, Steen, & de Keyser, 1999), as there is a lack of consensus regarding favorable vs. unfavorable poor outcome in terms of Rankin score. Dichotomization has also been criticized as being associated with a loss of information when determining the benefits derived from a particular rehabilitation intervention. For example, Lai and Duncan (2001) reported that 62% of patients included in their study experienced recovery represented by a shift of 1 or more Rankin grades in the first 3 months following stroke. If these shifts were between grades 0 and 1 or between 4 and 5, for example, no change would be reported using a dichotomized system of outcomes where favourable outcome was defined as MRS = 0, 1, and 2 and unfavourable as MRS = 3, 4 or 5. In a study from Weisscher, Vermeulen, Roos, and de Haan (2008), 15% of patients were classified as having a favorable outcome when it was defined as MRS = 0-1. Among these patients, 84% were able to perform outdoor activities. When favorable outcome was defined as a MRS = 0-2, 37% were classified as having a favorable outcome. However, among this group, only 56% were able to perform outdoor activities. Lai and Duncan (2001) have suggested that transition in Rankin grades may be more appropriate in the assessment of intervention benefit. Weisscher et al. (2008) stated that defining favorable and unfavorable outcomes is an arbitrary decision.

The authors suggested that if favorable outcome is expressed by the ability to perform outdoor activities then the score 0-1 should be chosen. However, if complex ADL are considered as the main outcome, then a score of 0-2 on the MRS should be considered the best dichotomization option. Sulter et al. (1999) suggest that an appropriate definition may be that poor outcome exists if any of the following occur: death, institutionalization due to stroke, MRS score >3, or Barthel Index score <60.

Time:
5-15 minutes (New & Bushbinder, 2006)

Subscales:
There are no subscales to the MRS.

Equipment:
Administration of the MRS does not require any specialized equipment.

Training:
No formal training is required to administer the MRS.

Alternative form of the Modified Rankin Scale (MRS)
  • Modified Rankin Scale-Structured Interview (MRS-SI) (Wilson et al., 2002).
  • Wilson et al. (2002) developed a structured interview to improve the inter-rater reliability of the MRS. The structured interview differs from the conventional guided interview for the MRS by defining specific questions to grade each category. The structured interview developed for the study consisted of 5 sections: (1) constant care (e.g. does the person require constant care?), (2) basic ADL (e.g. is assistance essential for eating, using the toilet, daily hygiene, or walking?), (3) instrumental ADL (e.g. is assistance essential for preparing a simple meal, doing household chores, looking after money, shopping, or traveling locally?), (4) limitations in participation in usual social roles (e.g. has there been a change in the person’s ability to participate in previous social and leisure activities?), and (5) checklist for the presence of common stroke symptoms (e.g. does the person have difficulty reading/writing, speaking or finding the right word, problems with balance/coordination, visual problems, numbness, difficulty with swallowing, or other symptom resulting from stroke?). Inter-rater reliability improved significantly after training in the structured interview (Wilson et al., 2005). Furthermore, the extent of disagreement between raters on the MRS-SI was less than what has been observed with the MRS. 
Client suitability

Can be used with:

Patients with stroke.

Should not be used with:

  • The MRS has not been evaluated for use with proxy respondents.
In what languages is the measure available?

The MRS is available in:

  • German (Berger et al., 1999)
  • Persian (Oveisgharan et al., 2006)
  • Dutch (e.g. Hop, Rinkel, Algra, & van Gijn, 1998).