ATTACHMENT #2: SUPPLEMENTARY NIHSS INSTRUCTIONS

The following material was taken (and modified slightly) from the NIHSS training materials for the NIH sponsored tPA-stroke trial.

The NIH Stroke Scale

I. Overview

The NIH Stroke Scale is a standardized neurological examination intended to describe the neurological deficits found in large groups of stroke patients participating in treatment trials. These instructions reflect primary concern for reproducibility. The goal is to have multiple examiners at different sites rate patients similarly. It is possible to challenge the scale on sub-items, and competent neurologists will disagree over the "best" method for testing some items in individual patients. Nevertheless, our interest in reproducibility among many observers in a large multicenter study is paramount, and to this end, all examiners at all sites must use the scale uniformly. We recognize that for some examiners, this means that some testing may be done one way for the study, and a different way in usual clinical practice. The consolation for this disparity is the knowledge that the reproducibility among examiners using this scale will (hopefully) be extremely high.

There are four general principals underlying the scale in its present form:

1. The most reproducible response is generally the first response. For example, on LOC questions, the patient is asked to state age and the current month. The patient who initially responds incorrectly, but later corrects himself, is scored as having given an incorrect response. This approach is critical, because we have no way of standardizing the myriad verbal and non-verbal cues that might be given to patients to promote a correction of an initially incorrect response.
2. It is not permissible to coach patients on any item unless specified in the instructions. This contradicts neurologic teaching, since we are generally interested in a patient's best possible performance. Again, standardization of coaching is not possible, and coaching must be avoided in the interest of reproducibility.
3. Some items are scored only if definitely present. For example, ataxia is scored as absent in the patient with hemiplegia, because it is not definitely present at the time of examination. Although somewhat counterintuitive to some physicians, the item must be scored this way to avoid ambiguity and ensure reproducibility.
4. Most importantly, record what the patient does, not what you think the patient can do even if the findings appear contradictory. Many times a competent examiner forms an impression of the patient's level of function, but this impression must not influence scoring. Scoring should include prior deficits except for the sensory item (see instructions)

II. Certification

Any investigator completing the NIH Stroke Scale for the trial must be certified.

Requirements for Certification.

Review of the NIH Stroke Scale Training Tape

Completion of NIH Stroke Scales for the five patients shown on the NIH Stroke Scale Certification Tape- #1

Submission of the five completed forms to the Coordinating Center for review

Approval by the Coordinating Center

Retention of Certification

Completion of the NIH Stroke Scales on the six patients shown on the NIH Stroke Scale Certification Tape #2 (approximately six months after the initial certification)

Submission of the six completed forms to the Coordinating Center for review.

Approval by the Coordinating Center

1. Level of Consciousness

Three items are used to assess the patient’s level of consciousness. It is vital that the items be asked in a standardized manner, as illustrated in the Stroke Scale training tape. Responses must be based on what the patient does first. Do not give credit if the patient corrects himself/herself and do not give any clues or coaching.

1a. Level of Consciousness

Instructions:

The investigator must choose a response, even if a full evaluation is prevented by such obstacles as an endotracheal tube, language barrier, orotracheal trauma/bandages. A 3 is scored only if the patient makes no movement (other than reflexive posturing) in response to noxious stimulation.

Comments:

Ask the patient two or three general questions about the circumstances of the admission. Also, prior to beginning the scale, it is assumed that the examiner will have queried the patient informally about the medical history. Based on the answers, score the patient using the 4-point scale on the Stroke Scale form. Remember not to coach. A score of 3 is reserved for the severely impaired patient who makes, at best, reflex posturing movements in response to repeated painful stimuli. If it is difficult to choose between a score of 1 or 2, continue to question the patient about historical items until you feel comfortable in assessing level of consciousness.

lb. LOC Questions

Instructions:

The patient is asked the month and his/her age. The answer must be correct - there is no partial credit for being close. Aphasic and stuporous patients who do not comprehend the questions will score 2. Patients unable to speak because of endotracheal intubation, orotracheal trauma, severe dysarthria from any cause, language barrier or any other problem not secondary to aphasia are given a 1. It is important that only the initial answer be graded and that the examiner not "help" the patient with verbal or non-verbal cues.

Comments:

Ask the patient "how old are you now" and wait for a response. Then ask "what month is it now" or "what month are we in now". Count the number of incorrect answers and do not give credit for being "close". Patients who cannot speak are allowed to write. Do not give a list of possible responses from which to choose the correct answer. This may coach the patient. Only the initial answer is graded. This item is never marked "untestable". (Note: On Certification Tape #1 an intubated patient was given a series of responses from which to choose, but the score for this patient would still be 1.) Deeply comatose (la=3) patients are given a 2.

lc. LOC Commands:

Instructions:

The patient is asked to open and close the eyes and then to grip and release the nonparetic hand. Substitute another one step command if the hands cannot be used. Credit is given if an unequivocal attempt is made but not completed due to weakness. If the patient does not respond to command, the task should be demonstrated to them (pantomime) and score the result (i.e., follows none, one or two commands). Patients with trauma, amputation, or other physical impediments should be given suitable one-step commands. Only the first attempt is scored.

Comments:

Say to the patient "open your eyes ... now close your eyes" and then "Make a fist ... now open your hand". Use the non-paretic limb. If amputation or other physical impediment prevents the response, use another suitable one step command. The priming phrase is not scored, and these are used only to set the eyes or hand in a testable position. That is, the patient may be asked first to open the eyes if they are closed when you begin the test. Scoring is done on the second phrase "close your eyes". Count the number of incorrect responses and give credit if an unequivocal attempt is made to perform the operative task, but is not completed due to weakness, pain or other obstruction. Only the first attempt is scored and the questions should be asked only once.

Item 2: Best Gaze

Instructions:

Only horizontal eye movements will be tested. Voluntary or reflexive (oculocephalic) eye movements will be scored but caloric testing is not done. If the patient has a conjugate deviation of the eyes that can be overcome by voluntary or reflexive activity, the score will be 1. If a patient has an isolated peripheral nerve paresis (CN III, IV or VI) score a 1. Gaze is testable in all aphasic patients. Patients with ocular trauma, bandages, pre-existing blindness or other disorder of visual acuity or fields should be tested with reflexive movements and a choice made by the investigator. Establishing eye contact and then moving about the patient from side to side will occasionally clarify the presence of a partial gaze palsy.

Comments:

The purpose of this item is to observe and score horizontal eye movements. To this end, use voluntary or reflexive stimuli and record a score of 1 if there is an abnormal finding in one or both eyes. A score of two is reserved for forced eye deviation that cannot be overcome by the oculocephalic maneuver. Do not do caloric testing. In aphasic or confused patients it is helpful to establish eye contact and move about the bed.

This item is an exception to the rules of using the first observable response and not coaching. In the patient who fails voluntary gaze, the oculocephalic maneuver, eye fixation, and tracking with the examiner's face, are used to provide stronger testing stimuli.

Item 3: Visual

Instructions:

Visual fields (upper and lower quadrants) are tested by confrontation, using finger counting or visual threat as appropriate. Patient must be encouraged, but if they look at the side of the moving fingers appropriately, this can be scored as normal. If there is unilateral blindness or enucleation, visual fields in the remaining eye are scored. Score 1 only if a clear-cut asymmetry, including quadrantanopia is found. If patient is blind from any cause score 3. Double simultaneous stimulation is performed at this point. If there is extinction patient receives a 1 and the results are also used to answer question 11.

Comments:

Visual fields are tested exactly as demonstrated in the training video. Use finger counting or movement to confrontation and evaluate upper and lower quadrants separately. A score of 3 is reserved for blindness from any cause, including cortical blindness. A score of 2 is reserved for a complete hemianopia, and any partial visual field defect, including quadrantanopia, scores a 1.

Item 4: Facial Palsy

Instructions:

Ask, or use pantomime to encourage the patient to show teeth or raise eyebrows and close eyes. Score symmetry of grimace in response to noxious stimuli in the poorly responsive or non-comprehending patient. If facial trauma/bandages, orotracheal tube, tape or other physical barrier obscures the face, these should be removed to the extent possible.

Comments:

Ask the patient "Show me your teeth ... now raise your eyebrows ... now close your eyes tightly". Assess the response to noxious stimulation in the aphasic or confused patient. A useful approach to scoring may be as follows: score a 2 for any clear-cut upper motor neuron facial palsy. Normal function must be clearly demonstrated to obtain the score of 0. Anything in between, including flattened nasolabial fold, is scored a 1. The severely obtunded or comatose patient; patients with bilateral paresis, patients with unilateral lower motor neuron facial weakness would receive a score of 3.

Items 5 & 6: Motor Arm and Leg

Instructions:

Each limb is tested in turn, beginning with the non-paretic arm, if known. The limb is placed in the appropriate position: extend the arm (palm down) 90 degrees (if sitting) or 45 degrees (if supine) and the leg 30 degrees (always tested supine). Drift is scored if the arm falls before 10 seconds or the leg before 5 seconds. The aphasic patient is encouraged using urgency in the voice and pantomime but not noxious stimulation. Only in the case of amputation or joint fusion at the shoulder or hip may the score be "9" and the examiner must clearly write the explanation for scoring as a "9".

Comments:

Perform the test for weakness as illustrated in the video. When testing arms, palms must be down. Count out loud to the patient, until the limb actually hits the bed or other support. The score of 3 is reserved for the patient who exhibits no strength whatsoever, but does minimally move the limb on command when it is resting on the bed. The aphasic patient may understand what you are testing if you use the nonparetic limb first. Do not test both limbs simultaneously. Be watchful for an initial dip of the limb when released. Only score abnormal if there is a drift after the dip.

Do not coach the patient verbally. Count out loud in strong voice and indicate count using your fingers in full view of the patient. Begin counting the instant you release the limb. (Note that on some of the video-illustrated patients, the examiners erroneously delay seconds before beginning to count).

When testing motor leg the patient must be in the supine position to fully standardize the effect of gravity. Note that the examiner is no longer asked to identify the paretic arm or leg. The examiner's assessment of the side of the stroke is given on the Treatment Form (Form 7).

Item 7:Limb Ataxia

Instructions:

This item is aimed at finding evidence of a unilateral cerebellar lesion. Test with eyes open. In case of visual defect, insure testing is done in the intact visual field. The finger-nose-finger and heel-shin tests are performed on both sides, and ataxia is scored only if present out of proportion to weakness. Ataxia is absent in the patient who cannot understand or is paralyzed. Although the use of untestable is discouraged, in the case of amputation, joint fusion or some fractures, the item may be scored "9", and the examiner must clearly write the explanation for not scoring. In case of blindness test by touching nose from extended arm position.

Comments:

Ataxia must be clearly present out of proportion to any weakness. Using the finger-nose-finger and the heel-test, count the number of ataxic limbs, up to a maximum of two. The aphasic patient will often perform the test normally if first the limb is passively moved by the examiner. Otherwise the item is scored 0 for absent ataxia. If the weak patient suffers mild ataxia, and you cannot be certain that it is out of proportion to the weakness, give a score of 0. Remember this is scored positive only when ataxia is present.

Item 8: Sensory

Instructions:

Sensation or grimace to pin prick when tested, or withdrawal from noxious stimulus in the obtunded or aphasic patient. Only sensory loss attributed to stroke is scored as abnormal and the examiner should test as many body areas (arms (not hands), legs, trunk, face] as needed to accurately check for hemisensory loss. A score of 2, "severe or total," should only be given when. A severe or total loss of sensation can be clearly demonstrated. Stuporous and aphasic patients will therefore probably score 1 or 0. The patient with brain stem stroke who has bilateral loss of sensation is scored 2. If the patient does not respond and is quadriplegic score 2. Patients in coma (item la= 3) are arbitrarily given a 2 on this item.

Comments:

Do not test limb extremities, i.e., hands and feet when testing sensation because an unrelated neuropathy may be present. Do not test through clothing.

Item 9:Best Language

Instructions:

A great deal of information about comprehension will be obtained during the preceding sections of the examination. The patient is asked to describe what is happening in the attached picture, to name the items on the attached naming sheet, and to read from the attached list of sentences. Be complete. Have the patient name all items on the naming sheet and read all phrases on the two reading sheets. Comprehension is judged from responses here as well as to all of the commands in the preceding general neurological exam. If visual loss interferes with the tests, ask the patient to identify objects placed in the hand, repeat, and produce speech. The intubated patient should be asked to write. The patient in coma (question la=3) will arbitrarily score 3 on this item. The examiner must choose a score in the patient with stupor or limited cooperation but a score of 3 should be used only if the patient is mute and follows no one step commands.

Comments:

It is anticipated that most examiners will be ready to score this item based on information obtained during the history taking and the 8 prior items. The attached picture and naming sheet therefore should be used to confirm your impression. It is common to find unexpected difficulties when the formal testing is done, and therefore every patient must be tested with the picture, naming sheet, and sentences. The score of 3 is reserved for the globally mute or comatose patient. Mild aphasia would score a 1. To choose between a score of 1 or 2 use all the provided materials; it is anticipated that a patient who missed more than two thirds of the naming objects and sentences or who followed only very few and simple one step commands would score a 2.

This item is an exception to the rule that the first response is used, since several different tools are used to assess language. The stroke scale form contains lengthy examples of the defects associated with each score because of the great potential for variability in answering this question.

Item 10: Dysarthria

Instructions:

If the patient is thought to be normal, an adequate sample of speech must be obtained by asking patient to read or repeat words from the attached list. If the patient has severe aphasia, the clarity of articulation of spontaneous speech can be rated. Only if the patient is intubated or has other physical barrier to producing speech, may the item be scored "9", and the examiner must clearly write an explanation for not scoring. Do not tell the patient why he/she is being tested.

Comments:

Use the attached word list in all patients and do not tell the patient that you are testing clarity of speech. It is common to find slurring of one or more words in patients one might otherwise score as normal. The score of 0 is reserved for patients who read all words without any slurring. Aphasic patients and patients who do not read may be scored based on listening to the speech that they do produce or by asking them to repeat the words after you read them out loud. The score of 2 is reserved for the patient who cannot be understood in any meaningful way, or who is mute.

On this question, normal speech must be identified to score a 0, so the unresponsive patient receives the score of 2.

Item 11: Extinction and inattention

Instructions:

Sufficient information to identify neglect may be obtained during the prior testing. If the patient has a severe visual loss preventing visual double simultaneous stimulation, and the cutaneous stimuli are normal, the score is normal. If the patient has aphasia but does appear to attend to both sides, the score is normal. The presence of visual spatial neglect or anosagnosia may also be taken as evidence of abnormality. Since the abnormality is scored only if present, the item is never untestable.

Comments:

This item is open to significant variation among examiners, and all neurologists have slightly different methods of assessing neglect. Therefore, to the extent possible, test only double simultaneous stimulation to visual and tactile stimuli and score 2 if one side extinguishes to both modalities, a 1 if only to one modality. If the patient does not extinguish, but does show other well-developed evidence of neglect, score a 1.

IV. Special Situations

In some cases, scoring may be difficult. This is particularly true in comatose or uncooperative patients. The following comments should help.

Coma

A patient with a 3 on Item la (Level of Consciousness) is considered to be in a coma. A patient suspected to be in coma should be stimulated by rubbing on the chest or by using a painful stimulus. A 3 is scored only if the patient makes no movement (other than reflexive posturing) in response to the noxious stimulation. Patients who appear to be in coma and who score less than 3 must be tested on all items.

For patients scoring a 3 on Item la, the remaining items should be scored as follows:

Item lb (LOC Questions) - Score 2.

Item lc (LOC Commands) - Score 2.

Item 2 (Best Gaze) - Patient can be in coma and have gaze palsy that can be overcome by moving the head. Thus the oculocephalic maneuver must be done and the patient scored.

Item 3 (Visual) - Test using bilateral threat.

Item 4 (Facial Palsy) - Score 3.

Items 5 and 6 (Motor Arm and Leg) - This is interpreted as the voluntary ability to attain a posture. Score 4 for both arm and leg.

Item 7 (Limb Ataxia) - Scored only if present, out of proportion to weakness. Score 0.

Item 8 (Sensory) - Score 2 (arbitrary).

Item 9 (Best Language) - Score 3.

Item 10 (Dysarthria) - Score 2.

Item 11 (Extinction and inattention) - Coma implies loss of all cognitive abilities. Score 2.

In the event that a patient refuses to perform the tasks in the course of the examination resulting in an item untested, a detailed explanation must be clearly written on the form. All untested items will be reviewed by the medical monitor and discussed with the examiner if necessary.

V. Calculating a Score

In computing a score, the following items should not be added to the total:

For Item 7 (Limb Ataxia) codes for affected sides (right and/or left arm and leg; 1=yes, 2=no, 9=untestable).

Any 9's.

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