Later Stage HD Assessments (LSA) is an observational, multinational study aiming at developing two assessments that can be used to measure critical milestones and events during the later stages of Huntington's disease (HD). An important aspect of the evaluation will be to assess whether the assessments can be administered to a companion either in-person or remotely (i.e. by phone contact with the companion). Therefore, these assessments will be evaluated for their internal consistency, reliability and validity. Once established, these assessments may be incorporated into a large scale, global observational study of HD and/or other HD clinical studies as well as use them for planning clinical trials.
Development of Assessments for Later Stage Huntington's Disease: UHDRS Structured Interview of Function and HD Clinical Status Questionnaire
The primary objective of this study is to evaluate the internal consistency, reliability and validity of two assessments: (1) UHDRS Structured Interview of Function (SIF) that incorporates the UHDRS Total Functional Capacity, Functional Assessment Scale, and Independence Scale (UHDRS TFC, FAS and IS), and (2) the HD Clinical Status Questionnaire (HDCSQ). There will be two study parts: Part 1 will measure the performance of the UHDRS SIF assessment compared to the original UHDRS TFC, FAS and IS using a cross-over design by collecting data from the Manifest HD gene expansion carrier participants (Manifest HDGEC Participants) and their companions (Companion Participants) via an in-person baseline visit and a follow-up visit by phone. Part 2 will assess the UHDRS SIF and the HDCSQ using a cross-sectional design by collecting data from the Companion Participants via a follow-up visit by phone. Participants of Part 1 are eligible to participate in Part 2.