Functional Rating Scale 2.0 (FuRST 2.0): A patient-reported outcome measure of function for Huntington's disease

Area of Science:

• Neurology
• Patient-Reported Outcomes
• Clinical Assessment

Background:

• Existing functional rating scales lack sensitivity to early functional decline in Huntington's disease (HD).
• Early detection of functional changes is crucial for timely intervention in HD progression.

Purpose of the Study:

• To develop a novel patient-reported outcome (PRO) measure, the Functional Rating Scale 2.0 (FuRST 2.0).
• To ensure FuRST 2.0 is sensitive to initial functional changes in Huntington's disease (HD), particularly stages 2 and mild stage 3.

Main Methods:

• Utilized standard assessment development methodology, including focus groups with HD patients and companions across six countries.
• Employed a Delphi panel and four rounds of cognitive interviews to refine scale comprehension and usability.
• Incorporated informal regulatory agency advice throughout the development process.

Main Results:

• Addressed concerns from patients and regulators regarding scale instructions, questions, response options, and overall comfort.
• Modified the scale's wording and format based on feedback to enhance clarity and user experience.

Conclusions:

• Developed the FuRST 2.0 official working document (OWD), a penultimate version of the scale.
• The OWD was created using a rigorous methodology involving patient input, expert consensus, and cognitive testing.
• Psychometric properties are currently under evaluation; the FuRST 2.0 OWD is available for use.