Mimoz 2007.

Methods	Single‐centre RCT (France) Study period: 14 May 2004 to 29 June 2006 Setting: surgical ICU
Participants	Adult inpatients Number of participants: not reported Number of catheters; 538 Age: mean age 57‐58 years (SD 18‐19) (reported separately in two groups) Sex: 67.4% men in chlorhexidine group and 75.7% men in povidone‐iodine group.
Interventions	Skin antisepsis using the following 2 regimens prior to CVC insertion and thereafter every 72 h. Intervention A: chlorhexidine gluconate, 0.025% benzalkonium chloride. Intervention B: 4% benzylic alcohol combined versus 5% povidone‐iodine in 70% ethanol.
Outcomes	Catheter colonisation Catheter‐related BSI Outcomes assessed at various points during in‐patient stay.
Notes	Funding source: this study was supported by Centre Hospitalier et Universitaire de Poitiers and unrestricted grants from Bayer HealthCare and Viatris Pharmaceuticals.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	'Methods', 'Randomisation': "The randomisation sequences were generated by computer and conveyed to the investigators by means of sealed envelopes, 1 for each catheter, with instructions to select envelopes in numerical order."
Allocation concealment (selection bias)	Low risk	'Methods', 'Randomisation': "The randomisation sequences were generated by computer and conveyed to the investigators by means of sealed envelopes, 1 for each catheter, with instructions to select envelopes in numerical order."
Blinding of participants and personnel (performance bias) All outcomes	High risk	'Methods', 'Randomisation': "Although it was not possible for the nurses and attending physicians to be blinded to the antiseptic agent used because of different colours of the 2 solutions (brown for the povidone‐iodine and colourless for the chlorhexidine‐based solution), the microbiologists who processed all of the cultures and the research team who reviewed the outcomes were unaware of the type of antiseptic solution used."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	'Methods', 'Randomisation': "Although it was not possible for the nurses and attending physicians to be blinded to the antiseptic agent used because of different colours of the 2 solutions (brown for the povidone‐iodine and colourless for the chlorhexidine‐based solution), the microbiologists who processed all of the cultures and the research team who reviewed the outcomes were unaware of the type of antiseptic solution used."
Incomplete outcome data (attrition bias) All outcomes	Low risk	There was 11% withdrawal, with a similar number of catheters excluded from analysis from the 2 groups. The authors have clearly stated the reasons for withdrawal and appeared to follow the intention‐to‐treat principle by analysing the available patient data in the originally assigned groups.
Selective reporting (reporting bias)	Low risk	Authors reported the 2 major outcomes stated in the 'Methods', namely, catheter colonisation and catheter‐related BSI, in sufficient details in the 'Results'.
Other bias	Low risk	None identified