How to Score the Neurostatus-EDSS

The Neurostatus-EDSS assessment should reflect signs and symptoms due to MS only. In case of doubt, the examining physician should assume a relation to MS and grade according to the definitions. However, if the signs/symptoms are clearly not due to MS, the subscore test must be graded as usual but labeled with either a “T” for a temporary symptom (e.g. transitory immobilization after limb fracture) or a “P” for a permanent symptom (e.g. leg amputation after accident). When calculating the appropriate FSS these values are not taken into consideration to determine the FSS.

T and P cannot be applied to the following fields:

• The Visual FS values “CC” and “SC”
• The Pyramidal FS values for all reflexes (including plantar, cutaneous and palmomental reflex)
• The Pyramidal FS values “Functional Tests”
• The Pyramidal FS value for the Overall Motor Performance (OMP)
• The Sensory FS values “Lhermitte’s sign” and Paraesthesia of UE, trunk and LE”
• The Bowel & Bladder values “Sexual dysfunction”

The following tests are optional and are not defined as missing data if not captured. Consequently, they have no impact on the calculation of any score (even if captured):

• The Visual FS values “cc” and “sc”
• The Pyramidal FS values “Functional Tests”
• The Sensory FS values “Lhermitte’s sign” and “Paraesthesia of EU, trunk and LE”
• The Bowel & Bladder values “Sexual dysfunction”
• The Ambulation values “Distance reported by patient” and “Time reported by patient”

The following tests are optional and are only defined as missing data if captured on one side only. If captured, they do have an impact on the calculation:

• The Visual FS values “Disc Pallor”
• The Pyramidal FS values “Palmomental reflex”

The following tests are not optional and are therefore defined as missing data if not captured as requested but have no impact on the calculation of any score:

• The cerebral FS values “Depression” and “Euphoria”

A FS score of 1, or “signs only” is noted when the examination reveals signs of which the patient is unaware, and which do not interfere with the patient’s normal daily activities. However, this general rule does not apply to the Visual, Bowel/Bladder and Cerebral FSs.

When determining the final FSS of the Visual and Bowel/Bladder Functional Systems, the FSS must be converted into a lower score according to the conversion-table provided in the Definitions Booklet. In Electronic Clinical Outcome Assessment (eCOA) systems using eEDSS the software usually does the conversion automatically.

Listed below are some tips for the FSS/EDSS calculation:

• If the patient’s signs/symptoms exceed the limits of a defined grade (either FSS or EDSS), you should choose the next higher FSS or EDSS Step, even though your exact grading combination (combinations of subscores towards FSS or FSS towards EDSS Step) is not mentioned in the Definitions Booklet (especially in the pyramidal and sensory chapters).
• In general, the FSS should not be lower than any of the subscores (although there are exceptions in brainstem, cerebellar and cerebral Functional Systems – see the Definitions Booklet). In addition, the EDSS Step should not be lower than the score of any individual FS (except for the Visual and Bowel/Bladder FSS before conversion).

What should you do if in case of restriction in the neurological examination?

• If there are previous known deficits in functions that are newly affected by a T or P labeling, the rater should use the values from the previous examination for the FSS calculation, or alternatively estimate the amount of MS impact on the deficit. Besides, he needs to add a comment to clarify the decision (both for paper version and eEDSS in eCOA).
• In case essential parts of the neurological assessment cannot be performed (for example the ambulation cannot be tested), the rater can try to determine the appropriate score by using the values from the last examination, as well as by asking the patient for a subjective report. If this is not possible, a valid EDSS cannot be determined.
• If the rater forgets any part of the neurological examination (subscores only), he can orientate himself with the values from the previous examination. If this is not possible and the subscore is mandatory, the rater can decide individually and use either the best or the worst value and clarify it in a comment (both for paper and electronic version). Please note that missing subscores in eCOA devices do not allow for the data to be submitted. If essential parts of the neurological assessment are forgotten, see previous paragraph.

There are some rules concerning crosschecks between different chapters and subscores.

Ambulation Score, pyramidal and cerebellar FSS:

If ambulation is assessed as ‘restricted’ (AS>0), the pyramidal and/or cerebellar FSS must be ≥2 to reflect this restriction on ambulation; otherwise, a comment needs to be added to explain the deviation from the definitions.

Muscle strength and overall motor performance (OMP)

If muscle strength in all muscle groups is normal (equal to a subscore of 5), OMP can only be 0 or 1. If any muscle strength subscore is not 5, OMP can only be 2.

Urinary retention and bladder catheterization:

According to the Neurostatus-EDSS rules, a severe urinary retention (subscore of 3 in urinary hesitancy and retention) or a loss of function (subscore of 3 in urinary hesitancy and retention) in general requires the use of bladder catheterization. The use of bladder catheterization should be reflected in the bladder catheterization subscore (either subscore of 1 or 2).

Lower limb strength and ability to walk:

If the BMRC value in one leg (LE) ≥ 0 and ≤ 2 and the Spasticity value in the same leg (LE) ≤ 2, then the Ambulation Score must be > 5.
If the BMRC value in both legs (LE) ≥ 0 and ≤ 2 and the Spasticity value in one or both legs (LE) ≤ 2, then the Ambulation Score must equal 7 or must be ≥ 9.

Gait ataxia and ability to walk:

If the Gait Ataxia value = 4, then the Ambulation Score must equal 7 or must be ≥ 9.