Please assess the completion status of the following clinical trial:

Trial Title: Natural History Study of Infants and Children With Developmental and Epileptic Encephalopathies

Study Design Characteristics:
- Allocation: None
- Intervention Model: None
- Observational Model: COHORT
- Primary Purpose: None
- Time Perspective: PROSPECTIVE
- Masking: None
- Phase: None
- Number of Arms: None

Eligibility Criteria:
Inclusion Criteria:~* Aged between 6 months and 60 months.~* Confirmed SCN1A mutation.~* Normal development prior to onset of first seizure as defined by the Centers for Disease -Control and Prevention (CDC 2019).~* Onset of seizures between age 3 and 15 months, inclusive.~Exclusion Criteria:~* Copy number variant of SCN1A, including SCN1A microdeletion, if affecting other genes.~* SCN1A mutation present on both alleles.~* Known pathogenic or clinically suspected mutation in a seizure-associated gene besides SCN1A.~* Confirmed mutation in a gene besides SCN1A that is known to increase the severity of the seizure phenotype.~* Known gain-of-function genetic mutation, as defined by functional studies, including p.Thr226Met.~* History of notable developmental deficit that was evident prior to seizure onset.~* Known central nervous system structural abnormality as found on magnetic resonance imaging or computed tomography scan of brain.~* Currently taking or has taken for 6 or more consecutive weeks anti-seizure medications (ASMs) at a therapeutic dose that are contraindicated in SCN1A-positive Dravet Syndrome, including sodium channel blockers.~* Known concomitant genetic mutation or clinical comorbidity that potentially confounds typical Dravet phenotype.

- Gender: ALL
- Minimum Age: 6 Months
- Maximum Age: 60 Months
- Healthy Volunteers: f

Study Arms:
- SCN1A-positive Dravet Syndrome (Type: None): Participants aged between 6 and 60 months of age who have SCN1A-positive Dravet Syndrome. Clinical, neurocognitive, laboratory, the burden of disease, and health care resource utilization will be assessed.

Based on this trial design, predict the completion outcome and termination type (if applicable).