Objective: Reduce central line-associated bloodstream infection (CLABSI) rates 15% over 12 months in children's hospital NICUs. Use orchestrated testing as an approach to identify important CLABSI prevention practices. Methods: Literature review, expert opinion, and benchmarking were used to develop clinical practice recommendations for central line care. Four existing CLABSI prevention strategies (tubing change technique, hub care monitoring, central venous catheter access limitation, and central venous catheter removal monitoring) were identified for study. We compared the change in CLABSI rates from baseline throughout the study period in 17 participating centers. Using orchestrated testing, centers were then placed into 1 of 8 test groups to identify which prevention practices had the greatest impact on CLABSI reduction. Results: CLABSI rates decreased by 19.28% from 1.333 to 1.076 per 1000 line-days. Six of the 8 test groups and 14 of the 17 centers had decreased infection rates; 16 of the 17 centers achieved >75% compliance with process measures. Hub scrub compliance monitoring, when used in combination with sterile tubing change, decreased CLABSI rates by 1.25 per 1000 line-days. Conclusions: This multicenter improvement collaborative achieved a decrease in CLABSI rates. Orchestrated testing identified infection prevention practices that contribute to reductions in infection rates. Sterile tubing change in combination with hub scrub compliance monitoring should be considered in CLABSI reduction efforts.