The Liverpool Seizure Severity Scale (LSSS) was developed to quantify the patient's own perceptions of changes in seizure severity. This was revised based on experience in the use of the original scale. The score was originally developed in Liverpool, England.


There are 12 statements that are answered if the person has experienced a seizure in the past 4 weeks.

(1) how severe most severe

(2) length of time blanked out

(3) smacking lips during a seizure

(4) confusion after the seizure

(5) duration of confusion

(6) falling to the ground

(7) headache

(8) feeling sleepy

(9) urinary incontinence

(10) tongue biting

(11) other injury

(12) time before able to return to previous activity


Response are 0 to 3, except for the final question which is 0 to 4.



• In the table on page 63, numbers are assigned to statements 1, 3, 4, 6, 7, 8, 9, 10 and 11 in a reversed order. The values shown reflect the reversal in Step 2 of Appendix B on page 63.


raw LSSS score =

= SUM(points for all 12 statements)


ICTAL score =

= (raw LSSS score) / 40 * 100



• minimum raw score: 0

• maximum raw score: 40

• minimum ICTAL (adjusted) score: 0

• maximum ICTAL (adjusted) score: 100

• The higher the ICTAL score, the more severe the seizures.

• If no seizures have occurred in the past 4 weeks, the ICTAL score is 0.

• If 4 or more questions are not answered, then the ICTAL score is "missing".

• If 1 to 3 questions are not answered, then calculate the average score for the questions answered and then multiply this by 12 to get the raw LSSS score.



• The authors tested the revised scale on archival data from an observational study.

• They felt that the scale was reliable, showed construct validity and was responsive to changes in the patient's clinical status.


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