Figure 2. Hierarchical clustering analysis of disease progression using consistent worsening of physical and cognitive function using the multiple sclerosis functional composite.

Consistent worsening was determined by using the progression 2 definition (at least 6/8 worse than baseline; Table 1). Study subjects are on columns. Red indicates “progressor”, blue indicates lack of progression. The data are from 2-year studies in SPMS (a) and PPMS (b) subjects randomized to placebo in the IMPACT [8] and OLYMPUS [9] clinical trials.