Capturing what matters: Patient-reported LGI1-ANTibody encephalitis outcome RatiNg scale (LANTERN)

Area of Science:

• Neurology
• Immunology
• Patient-Reported Outcomes

Background:

• LGI1-antibody encephalitis (LGI1-Ab-E) often presents with good clinician-rated outcomes, yet many patients experience long-term debilitating symptoms.
• Existing assessments may not fully capture the persistent symptom burden experienced by individuals with LGI1-Ab-E.

Purpose of the Study:

• To develop and validate the LGI1-Antibody Encephalitis Rating (LANTERN) scale, a disease-specific patient-reported outcome measure (PROM).
• To quantify the frequency and severity of symptoms and impact on daily living in LGI1-Ab-E.

Main Methods:

• A three-stage, participant-driven mixed-methods approach including interviews, cognitive debriefing, and psychometric surveys.
• Development involved item generation from 73 initial items, cognitive debriefing with 15 participants, and a final survey with 66 patients and 32 relatives.
• Analyses included exploratory factor analysis, sensitivity testing, and multiple internal/external validations.

Main Results:

• The LANTERN scale was distilled to a 41-question survey assessing 19 symptoms and 6 activities of daily living (ADL) across physical, cognitive/behavioral, and ADL domains.
• The final questionnaire demonstrated strong internal reliability (Cronbach alpha: 0.85-0.91) and excellent test-retest correlations (0.81-0.98).
• High correlations were observed with relative-completed questionnaires (R=0.73-0.85) and predefined external measures.

Conclusions:

• The LANTERN scale is a valid and reliable PROM for LGI1-Ab-E, exhibiting initial content, structural, and construct validity.
• It provides a tailored, efficient, and sensitive method for assessing symptom burden in LGI1-Ab-E patients.
• LANTERN is suitable for use in both clinical practice and clinical trials to better understand patient experiences.