Myotonic Dystrophy Health Index: initial evaluation of a disease-specific outcome measure

Muscle Nerve. 2014 Jun;49(6):906-14. doi: 10.1002/mus.24097.

Abstract

Introduction: In preparation for clinical trials we examine the validity, reliability, and patient understanding of the Myotonic Dystrophy Health Index (MDHI).

Methods: Initially we partnered with 278 myotonic dystrophy type-1 (DM1) patients and identified the most relevant questions for the MDHI. Next, we used factor analysis, patient interviews, and test-retest reliability assessments to refine and evaluate the instrument. Lastly, we determined the capability of the MDHI to differentiate between known groups of DM1 participants.

Results: Questions in the final MDHI represent 17 areas of DM1 health. The internal consistency was acceptable in all subscales. The MDHI had a high test-retest reliability (ICC = 0.95) and differentiated between DM1 patient groups with different disease severities.

Conclusions: Initial evaluation of the MDHI provides evidence that it is valid and reliable as an outcome measure for assessing patient-reported health. These results suggest that important aspects of DM1 health may be measured effectively using the MDHI.

Keywords: muscle disease; myotonic dystrophy type-1; patient-relevant; patient-reported outcome measure; therapeutic trial, quality of life.

Publication types

  • Evaluation Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Cost of Illness
  • Disability Evaluation*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Myotonic Dystrophy / diagnosis*
  • Outcome Assessment, Health Care / methods*
  • Patient Outcome Assessment*
  • Reproducibility of Results
  • Self Report / standards
  • Severity of Illness Index*
  • Surveys and Questionnaires / standards
  • United States