PF4 and deep vein thrombosis: In multivariable models, PF4 test positivity was associated with a higher risk of DVT (adjusted OR, 2.32 [95% CI, 1.81 to 2.95]), PE (adjusted OR, 2.75 [95% CI, 2.08 to 3.63]), and a composite of any thrombosis (adjusted OR, 1.86 [95% CI, 1.51 to 2.30]).