Thomas 1989.

Methods	Parallel, quasi‐randomised controlled trial
Participants	63 neonates requiring IV fluids via peripheral venous line Mean gestation: 34.13 ‐ 34.91 weeks Mean birth weight: 2230 ‐ 2350 gm No exclusions
Interventions	Experimental group: 0.2 micron intravenous filter (N = 30) Control group: No filter but extension set substituted for filter (N = 33) Administration sets changed every 24 hours in treatment and control groups
Outcomes	1. Duration of cannula patency 2. Extravasation 3. Leaking at infusion site 4. Number of catheter insertions
Notes	Sample size calculation: Not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Each baby that required intravenous infusion was entered into the study with alternate babies having an in‐line filter
Allocation concealment (selection bias)	High risk	No
Blinding (performance bias and detection bias) All outcomes	High risk	No
Blinding of participants and personnel (performance bias) All outcomes	High risk	No
Blinding of outcome assessment (detection bias) All outcomes	High risk	Not described
Incomplete outcome data (attrition bias) All outcomes	Low risk	No missing outcome data
Selective reporting (reporting bias)	Unclear risk	We were unable to obtain the study protocol