Figure 2. Severity of symptoms. The correlation between p75^ECD/ml of urine and the Revised ALS Functional Rating Scale (ALSFRS-R). An increase in ALSFRS-R highlights a decrease in severity of symptoms. It focuses on physical symptoms, such as one’s ability to swallow, climb stairs, breathe and use of utensils. Each function is rated from 0 (no ability) to 4 (normal for the participant). (A) pg p75^ECD/ml or urine (r=−0.371, p≤0.0004, 95% CI (−0.543 to –0.169), equation of the line Y=−0.000371*X+39.36 and R²=0.119). (B) ng p75^ECD/mg normalised to creatinine. (r=−0.625, p≤0.0001, 95% CI (−0.741 to –0.473), equation of the line Y=1.221*X+45.67 and R²=0.365). : : ALS, amyotrophic lateral sclerosis; ECD, extracellular domain.