There were also no significant correlations between baseline CXCL4 and age, or disease duration, as measured by the onset of the first Raynaud’s phenomenon symptom (r = −0.10, P = 0.24), or as measured by the onset of the first non-Raynaud’s phenomenon symptom attributable to SSc (r = 0.040, P = 0.64). Here, PF4 is linked to systemic sclerosis.