Mimoz 1996.

Methods	Single‐centre RCT (France) Study period: 1 July 1992 to 31 October 1993 Setting: surgical‐trauma ICU
Participants	Consecutive patients aged 18 years and above who were scheduled to receive a non‐tunnelled central venous catheter, an arterial catheter or both Number of participants: not reported Number of catheters; 158 Age: mean age from 51 to 54 years (SD 18 to 19)(reported separately in two groups) Sex: not reported
Interventions	Comparison of the following 2 skin antiseptic regimens prior to catheter insertion and every 48 h post insertion. Intervention A: 0.25% chlorhexidine+ 0.025% benzalkonium Intervention B: 10% povidone‐iodine
Outcomes	Catheter colonisation Catheter‐related BSI Outcomes assessed at various points during in‐patient stay.
Notes	Trialists studied both arterial catheters and CVCs. They did not report data separately for CVC and arterial catheters except for the outcomes of catheter colonisation per 1000 catheter‐days and catheter‐related sepsis per 1000 catheter‐days. Funding source: funded in part by Les Laboratoires Nicholas, Gaillard, France.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	'Materials and methods', 'Randomisation procedure': "Each patient requiring at least one catheter was randomly allocated to one of two groups by drawing envelopes from an urn."
Allocation concealment (selection bias)	Unclear risk	'Materials and methods', 'Randomisation procedure': ""Each patient requiring at least one catheter was randomly allocated to one of two groups by drawing envelopes from an urn." It was unclear who drew the envelopes and when. It was also unclear whether the envelops were sealed and opaque. If the envelop was drawn by the investigator involved in the enrolment, there was a high risk of violating allocation concealment, for example, by redrawing.
Blinding of participants and personnel (performance bias) All outcomes	High risk	'Materials and methods', 'Blood cultures': "Although it was not possible for the research team to be blinded to the antiseptic agents used, the research microbiologist who processed all cultures had no knowledge of the antiseptic group to which the catheter had been assigned."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	'Materials and methods', 'Blood cultures': "Although it was not possible for the research team to be blinded to the antiseptic agents used, the research microbiologist who processed all cultures had no knowledge of the antiseptic group to which the catheter had been assigned."
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	There was no information on post randomisation withdrawals, nor any description on the use of intention‐to‐treat analysis.
Selective reporting (reporting bias)	Low risk	Authors reported the major outcomes stated in the 'Methods', namely catheter colonisation and catheter related sepsis, in sufficient details in the 'Results'. The authors provided separate data for CVCs and arterial catheters for the outcomes of catheter colonisation per 1000 catheter‐days and catheter‐related sepsis per 1000 catheter‐days.
Other bias	Low risk	None identified