Snydman 1987.

Methods	Alternately allocated controlled clinical trial
Participants	170 adult patients admitted to the medical and surgical ICUs receiving IV therapy for the required period Medical and surgical ICUs, USA
Interventions	Administration set changes at 48 or 72 hours
Outcomes	IR‐BSI CR‐BSI All‐cause BSI
Notes	Exclusions: previously enrolled in study or receiving blood products, PN or lipids. Confounders: The no. of burettes per line was statistically lower in the 72 hour group Central catheters: 27% PN: 0% Loss to follow‐up: 52%
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Poor random sequence generation Quote: "alternatively assigned" (abstract)
Allocation concealment (selection bias)	High risk	Easily predictable, inadequate concealment
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Not discussed, but not feasible in the study design
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not discussed, but not feasible in the study design
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Phlebitis measures were undertaken by staff blinded to culture results, but not known if they were blinded to the group Not discussed whether outcome assessors were blinded during cultures
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No discussion of attrition and missed cultures Originally 356 enrolled (176/180) but (71/115) dropped as discharged/died < 48/72 hours Imbalanced groups n = 105 (48 hours), n = 62 (72 hours)
Selective reporting (reporting bias)	Low risk	No pre‐protocol
Other bias	High risk	Results given per AS, not per participant 1.5 days longer ICU stay for 72 hour group Higher antibiotic courses in the 48 hour group Imbalanced AS cultured (745/449) between groups

AS: administration set, BSI: bloodstream infection, cfu: colony forming units, CR‐BSI: catheter‐related bloodstream infection, CVC: central venous catheter, h: hours, ICU: Intensive Care Unit, IR‐BSI: infusate‐related bloodstream infection, IV: intravenous, NICU: Neonatal Intensive Care Unit, no.: number, PN: parenteral nutrition.