The Myotonic Dystrophy Type 2 Health Index (MD2HI): A Multifactorial, Disease-specific, Patient-reported Outcome Measure for Use in Therapeutic Trials
Charlotte Engebrecht1, Spencer Rosero1, Jennifer Weinstein1, Jamison Seabury1, Anika Varma1, Shaweta Khosa1, Christina Shupe1, Charlotte Irwin1, Alicia Brocht1, Chad Heatwole1
1University of Rochester Center for Health + Technology
Objective:
To develop and validate the Myotonic Dystrophy Type 2 Health Index (MD2HI), a disease-specific, patient-reported outcome (PRO) measure for use in myotonic dystrophy type 2 (DM2) therapeutic trials and clinical monitoring.
Background:
There is a need for reliable, sensitive, and disease-specific PROs that are capable of detecting clinically relevant changes in DM2 health over time. The U.S. Food and Drug Administration (FDA) has encouraged the use of patient-reported outcome measures as an effective mechanism to support drug-labeling claims. This research describes the development and validation of a novel, multifactorial PRO, known as the MD2HI.
Design/Methods:
We conducted semi-structured qualitative interviews and a national cross-sectional study in individuals with DM2 to determine the most prevalent and impactful symptoms. We selected questions for the MD2HI based on their high relevance to individuals with DM2 and their potential responsiveness to therapeutic intervention. We then conducted beta testing of the MD2HI with individuals with DM2 to determine the instrument’s clarity, ease of use, and relevance to the DM2 population. Subsequently, we performed test-retest reliability, known groups validity, and factor analysis to further optimize and validate the final version of the MD2HI.
Results:
Fifteen individuals with DM2 participated in qualitative interviews and 74 participants completed the cross-sectional study. We conducted beta testing with 20 participants, followed by test-retest evaluation of the instrument with 24 individuals with DM2. These results demonstrated that the MD2HI is comprehensive, highly relevant, and reliable. The MD2HI contains 17 subscales that measure the multifactorial disease burden experienced by individuals with DM2.
Conclusions:
The development and validation of the MD2HI provides clinicians and researchers with a highly sensitive and responsive instrument that has the ability to measure clinically relevant changes in how a patient feels and functions over time or in response to therapeutic intervention.