Characteristics of the studies included.

Introduction
The prevalence of catheter-associated bloodstream infections (CLABSI) is high and is a severe health problem associated with an increase in mortality and elevated economic costs. There are discrepancies related to the risk factors of CLABSI since the results published are very heterogeneous and there is no synthesis in the description of all the predisposing factors.
Objective
We aimed to perform a systematic review and meta-analysis to synthesize and establish the risk factors predisposing to CLABSI reported in the literature.
Method
This is a systematic review of observational studies following the PRISMA recommendations. MEDLINE and CINAHL databases were searched for primary studies from 2007 to 2021. The protocol was registered in PROSPERO CRD42018083564.
Results
A total of 654 studies were identified, 23 of which were included in this systematic review. The meta-analysis included 17 studies and 9 risk factors were analyzed (total parenteral nutrition (TPN), chemotherapy, monolumen and bilumen catheters, days of catheterization, immunosuppression, kidney disease and diabetes mellitus) due to the homogeneity of their definitions and measurements. The risk factors found to increase the probability of developing CLABSI were TPN, multilumen devices, chemotherapy treatment, immunosuppression and the number of days of catheterization. On the other hand, monolumen devices presented a lower likelihood of triggering this infection.