# Estimating a preference-based index for patients with myasthenia gravis from the MGQoL-6D measure

## TL;DR

This study created a scoring system to estimate quality of life for myasthenia gravis patients using a Chinese survey.

## Contribution

Developed a utility-based scoring system for the MGQoL-6D in Chinese myasthenia gravis patients.

## Key findings

- Utility decrements were largest for emotion, social activity, and hobbies.
- MGQoL-6D scores ranged from -0.559 to 1, showing wide variability in health states.
- Conditional logistic regression produced monotonic utility estimates for health states.

## Abstract

Myasthenia gravis is a chronic neuromuscular disease that causes weakness. It’s uncertain whether generic health instruments can adequately capture its impact. This study aimed to develop a scoring system to generate utility values for all health states defined by the myasthenia gravis quality of life 6-dimension (MGQoL-6D) classification in Chinese patients with myasthenia gravis (MG).

The data used in this study were obtained from a web-based cross-sectional study conducted in China. Patients with MG were invited to complete an online discrete choice experiment (DCE) survey. Each participant completed 10 randomly assigned choice pairs from a set of 40 choice pairs, with each pair comprising two health states and a duration attribute. Conditional logistic regression analysis was employed to analyse the data, which included responses from 300 patients.

Utility decrements estimated by conditional logit regression were generally monotonic, with the largest decrements observed for emotion (− 0.419), social activity (− 0.323), and hobbies and fun activities (− 0.323). The MGQoL-6D utility scores ranged between − 0.559 and 1.

This study established utility weights for the MGQoL-6D that can facilitate cost-utility analyses related to MG-related health interventions and technologies.