CBCL: 99-item questionnaire measures specific behavioral problems or developmental delays, answered by a parent/legal guardian or suitable caregiver. Each item were rated using 3-point scale (0=Not True, 1=Somewhat/Sometimes True, 2=Very True/ Often True) to indicate how often or typical the behavior was. The 99 items were combined to yield scores for 8 problem area scales (emotionally reactive, anxious/depressed, somatic complaints, withdrawn, sleep problems, attention problems, aggressive behavior, and other problems) and 3 summary scores (internalizing, externalizing, and total problems). Total Problem score was sum of all the problem areas plus 1 additional item, ranging from 0 to 198. Total raw scores are converted to t-scores with mean of 50 and standard deviation (SD) of 10. T-scores were standardized test scores that indicate same degree of elevation in problems relative to the normative sample of peers. Higher scores were indicative of more problems.

The full analysis set for primary efficacy variable included randomized participants who received rufinamide or any other approved add-on AED of the investigator's choice and had baseline and at least 1 postdose cognition measurement. Participants who were evaluable for this outcome measure at given time period were included for assessment.

CBCL: 99-item questionnaire measures specific behavioral problems or developmental delays, answered by a parent/legal guardian or suitable caregiver. Each item were rated using 3-point scale (0=Not True, 1=Somewhat/Sometimes True, 2=Very True/ Often True) to indicate how often or typical the behavior was. The 99 items were combined to yield scores for 8 problem area scales (emotionally reactive, anxious/depressed, somatic complaints, withdrawn, sleep problems, attention problems, aggressive behavior, and other problems) and 3 summary scores (internalizing, externalizing, and total problems). Total Problem score was sum of all the problem areas plus 1 additional item, ranging from 0 to 198. Total raw scores are converted to t-scores with mean of 50 and standard deviation (SD) of 10. T-scores were standardized test scores that indicate same degree of elevation in problems relative to the normative sample of peers. Higher scores were indicative of more problems.

The full analysis set for primary efficacy variable included randomized participants who received rufinamide or any other approved add-on AED of the investigator's choice and had baseline and at least 1 postdose cognition measurement. Participants who were evaluable for this outcome measure at given time period were included for assessment.

Withdrawal from either rufinamide or other AED was due to the occurrence of an adverse event or for lack of efficacy. Data was obtained till Week 106 and was extrapolated using Kaplan-Meier method to determine the overall survival time (in weeks) to withdrawal from treatment (excluding taper) due to an adverse event or lack efficacy.

The full analysis set for other efficacy variable included randomized participants who received rufinamide or any other add-on AED of the investigator's choice and had a baseline efficacy assessment and at least 1 post baseline efficacy assessment. Participants who were evaluable at a given time point were included for this assessment.

The frequency per 28 days was defined as (S/D)*28 where, S was equal to the sum of the seizures reported in the participant seizure diary during the specified time interval and D was equal to the number of days with non-missing data in the participant seizure diary for the specified study phase. The number of seizures was assessed and recorded by the participant's parent(s)/caregiver(s) in the participant seizure diary.

The full analysis set for other efficacy variable included randomized participants who received rufinamide or any other add-on AED of the investigator's choice and had a baseline efficacy assessment and at least 1 postbaseline efficacy assessment. Participants evaluable for this outcome measure at given time period were included for assessment.

The frequency per 28 days was defined as (S/D)*28 where, S was equal to the sum of the seizures reported in the participant seizure diary during the specified time interval and D was equal to the number of days with non-missing data in the participant seizure diary for the specified study phase. The number of seizures was assessed and recorded by the participant's parent(s)/caregiver(s) in the participant seizure diary.

The full analysis set for other efficacy variable included randomized participants who received rufinamide or any other add-on AED of the investigator's choice and had a baseline efficacy assessment and at least 1 postbaseline efficacy assessment. Participants evaluable for this outcome measure at given time period were included for assessment.

Worsening of seizures was summarized by the incidence of participants with doubling in total seizure frequency, doubling in frequency of major seizures (generalized tonic-clonic, drop attacks), or occurrence of new seizure type during each successive 3 to 4 month visit interval of the Maintenance Period relative to baseline.

The full analysis set for other efficacy variable included randomized participants who received rufinamide or any other add-on AED of the investigator's choice and had a baseline efficacy assessment and at least 1 postbaseline efficacy assessment.

CBCL: 99-item questionnaire, measures behavioral problems/developmental delays, answered by parent/guardian/caregiver. Each item rated on 3-point scale (0=Not True,1=Somewhat/Sometimes True, 2=Very/Often True). 99 items were combined to give scores for 8 problem area scales, where 1 for each 8 syndrome (emotionally reactive, anxious/depressed, somatic, withdrawn, sleep, attention, aggressive behavior, and other problems) were calculated, range: 0 (normal) to 16 (clinical behavior) and 3 summary scores (internalizing, externalizing, and total problems). All 3 summary scores reported scaled to T-scores. Total Problem score was sum of all the problem areas plus 1 additional item, ranging from 0 to 198. Total raw score were converted to t-scores with mean of 50 and SD of 10. T-scores were standardized test scores that indicate same degree of elevation in problems relative to normative sample of peers. Higher scores were indicative of more problems.

The full analysis set for other efficacy variable included randomized participants who received rufinamide or any other approved add-on AED of the investigator's choice and had a baseline efficacy and at least 1 postbaseline efficacy assessment. Participants evaluable for this outcome measure at given time period were included for assessment.

LDS, a caregiver-administered survey consisted of 8-item questionnaire and vocabulary list of 310 words organized within 14 semantic categories. List contained high frequency words (e.g. more), less common words (e.g. hamburger), and lexical chunks (e.g. Sesame Street). Average LDS score, calculated by dividing total number of words across all valid phrases by number of phrases with greater than (>) 0words; for participants with no words, average was 0. This value was compared to standardized chart to obtain percentile rating. LDS provided 2 scores: average phrase length (number of words/phrase) and number of endorsed vocabulary words. LDS phrase length was categorized into delay (less than or equal to [<=] 20th percentile) and no delay (>20th percentile). LDS vocabulary was categorized into delay(<=15th percentile)and no delay(>15th percentile). Both raw scores were used to provide 2 normative scores based on child's age in months. Higher scores indicated better language development.

The full analysis set for other efficacy variable included randomized participants who received rufinamide or any other approved add-on AED of the investigator's choice and had a baseline efficacy and at least 1 postbaseline efficacy assessment. Participants evaluable for this outcome measure at given time period were included for assessment.

The QoLCE was a 76-item questionnaire designed specifically to measure quality of life in children with epilepsy. QOLCE consists of 16 quality of life subscales (14 multi-item and 2 single item). Each subscales had number of items or questions with responses as excellent, very good, good, fair, and poor. They were changed to 1, 2, 3, 4, and 5 as per instructions. Then changed on a scale of 100, where 1 is equal to (=) 0, 2=25, 3=50, 4=75, and 5=100. Items corresponding to each subscale were marked and there mean score was score of that subscale. The form was completed by a parent or caregiver who interacted with the child on a consistent, daily basis and took about 20 to 30 minutes to complete. The higher the score, the better the child's quality of life.

The full analysis set for other efficacy variable included randomized participants who received rufinamide or any other add-on AED of the investigator's choice and had a baseline efficacy assessment and at least 1 postbaseline efficacy assessment. Participants evaluable for this outcome measure at given time period were included for assessment.

The QoLCE was a 76-item questionnaire designed specifically to measure quality of life in children with epilepsy. QOLCE consists of 16 quality of life subscales (14 multi-item and 2 single item). Each subscales had number of items or questions with responses as excellent, very good, good, fair, and poor. They were changed to 1, 2, 3, 4, and 5 as per instructions. Then changed on a scale of 100, where 1=0, 2=25, 3=50, 4=75, and 5=100. Items corresponding to each subscale were marked and there mean score was score of that subscale. The form was completed by a parent or caregiver who interacted with the child on a consistent, daily basis and took about 20 to 30 minutes to complete. The higher the score, the better the child's quality of life.

The full analysis set for other efficacy variable included randomized participants who received rufinamide or any other approved add-on AED of the investigator's choice and had a baseline efficacy and at least 1 postbaseline efficacy assessment. Participants evaluable for this outcome measure at given time period were included for assessment.