Figure 1From: Fatigue in myasthenia gravis: is it more than muscular weakness? Estimated analytical model. We assumed that every variable on a “lower” level could be explained by variables higher in the hierarchy (i.e., variables at Level 4 could be explained by all variables at Levels 1 – 3). BMI = body mass index, AChEI = acetylcholine-esterase inhibitor.Back to article page