The percent change (increase or decrease) from baseline in 28-day seizure frequency during the maintenance period. Seizure frequency will be calculated as the total number of seizures divided by the number of days with seizure data, multiplied by 28.

The Pediatric Epilepsy Side Effects Questionnaire (PESQ) is a rating scale to assess pediatric participant-reported side effects associated with anti-seizure medication treatment. Each side-effect is rated on a 6-point Likert scale as follows: (1) - "Not present", (2) - "Low severity", (3) - "Low-moderate severity", (4) - "Moderate severity", (5) - "Moderate-high severity", (6) - "High severity". Higher scores indicated worse side-effects.

The Clinical Global Impression of Improvement (CGI-I) is a 7-point Likert scale used to rate the overall change in seizure control, behaviour, safety and tolerability after transitioning to Epidiolex relative to baseline. The participant's overall improvement is rated by the clinician and caregiver as: 1- "very much improved", 2- "much improved', 3- "minimally improved", 4- "no change", 5- "minimally worse", 6- "much worse", and 7- "very much worse". Higher scores indicate worse condition.

The Clinical Global Impression of Change in Seizure Intensity/Duration (CGI-CSID) is a 7-point Likert scale used to rate the overall change in seizure intensity and/or duration after transitioning to Epidiolex relative to baseline. The participant's overall improvement is rated by the clinician and caregiver as: 1- "very much improved", 2- "much improved', 3- "minimally improved", 4- "no change", 5- "minimally worse", 6- "much worse", and 7- "very much worse". Higher scores indicate worse condition.

The Quality of Life in Childhood Epilepsy Questionnaire (QOLCE-55) is a caregiver-reported questionnaire that evaluates quality of life in epileptic children. It contains 55 questions that measure quality of life in 4 areas: cognitive functioning, emotional functioning, social functioning, and physical functioning. Each question is rated on a 5-point Likert scale, with the option to answer "not applicable" as follows: (1) - "All of the time", (2) - "Most of the time", (3) - "Some of the time", (4) - "A little of the time", (5) - "None of the time", (6) - Not applicable. Higher scores indicate higher health-related quality of life.

The Measure Yourself Medical Outcome Profile 2 (MYMOP2) questionnaire is a scale that allows participants or caregivers to identify the problem(s) that are most important to them/the participant, and rate the severity of the problem (s) on a 7-point Likert scale ranging from 0 (as good as it can be) to 6 (as bad as it could be). Higher scores indicate worse problems.

The Children's Sleep Habit Questionnaire (CSHQ) is a caregiver-reported questionnaire to measure sleep behaviours in children. The questionnaire has 45 questions about bedtime resistance, sleep onset delay, sleep duration, sleep anxiety, night wakings, parasomnias, sleep disordered breathing, and daytime sleepiness. Each question is rated on a 3-point Likert scale as follows: (1) - "Usually (5 or more times in a week)", (2) - "Sometimes (2-4 times in a week)", (3) - Rarely (never or 1 time during a week). A higher score indicates more sleep problems.

The number of dose increases in anti-seizure medications (ASMs), including Epidiolex, due to worsening seizure burden or other factors.

The number of dose increases in anti-seizure medications (ASMs), including Epidiolex, due to adverse events or other factors.

Adverse events of special interest (AESIs) include: somnolence, sedation, appetite changes, gastro-intestinal upset (including diarrhea and vomiting), and transaminase elevations. Frequency of AESIs will be measured by determining the total number of AESIs experienced throughout the treatment period of the study.

Adverse events of special interest (AESIs) include: somnolence, sedation, appetite changes, gastro-intestinal upset (including diarrhea and vomiting), and transaminase elevations. The severity of AESIs will be assessed as: "Mild - Events require minimal or no treatment and do not interfere with the participant's daily activities", "Moderate - Events result in a low level of inconvenience or concern", or "Severe - Events interrupt a participant's usual daily activity and may require therapy or other treatment". The total number of mild, moderate and severe AESIs experienced throughout the treatment period of the study will be determined.

Adverse events of special interest (AESIs) include: somnolence, sedation, appetite changes, gastro-intestinal upset (including diarrhea and vomiting), and transaminase elevations. The duration of AESIs will be measured by calculating the length of individual AESIs experienced throughout the treatment period of the study.

The withdrawal rate will be determined as the percentage of participants who withdraw from the study and discontinue Epidiolex due to adverse events.

The percent change (increase or decrease) from baseline in 28-day seizure rescue medication use during the maintenance period. Rescue medication frequency will be calculated as the total number of doses of rescue medication administered divided by the number of days with diary data, multiplied by 28.

The Columbia-Suicide Severity Rating Scale (C-SSRS) assess the risk of suicidal ideation and behaviour. The questions are divided into categories related to ideation (thoughts) and behaviour (actions). Higher scores indicate more serious/worse suicidal ideation or behaviors.

The switching questionnaire consists of two multiple choice questions, along with an open-ended question designed to understand the caregiver's primary and secondary reasons for transitioning their child from 'artisanal' CBD to Epidiolex.