“…Estimates vary widely, from 0.3% 17,18 to 56%, 18 with the largest retrospective reviews supporting incidence rates of 2.5% and 3.9% (2,063 and 813 PICC insertions, respectively), confirmed by ultrasound 19,20 and/ or venography. 19 In a multivariate analysis, Grove et al 20 noted that only catheter diameter was predictive of thrombosis, with thrombosis rates of 1%, 6.6%, and 9.8% for 4-French (F), 5-F, and 6-F catheters, respectively. Chemaly et al 19 noted a time-dependent relationship to PICC-associated thrombosis with 34%, 55%, and 75% of events occurring by the end of the first, second, and third weeks after insertion, respectively.…”