Hanifi 2017.

Study characteristics
Methods	Study design: 2‐arm parallel‐group RCT Location: Iran Number of centres: 1 Study period: Oct 2013 to March 2014 Funding source: Zanjan University of Medical Sciences
Participants	Setting: ICU Inclusion criteria: The patient should undergo mechanical ventilation for at least 12 hours, being in the age range of 18 to 70 years, no history of pneumonia and aspiration during the hospitalisation, or chemotherapy, and no maxillofacial fractures, scalds, pregnancy, anaemia, alcohol intoxication, or a recent myocardial infarction Exclusion criteria: Separation from the mechanical ventilation before the end of the study period, vomiting during the use of gastrointestinal tract, death, or being dissuaded from continuing in any part of the study either by the patients’ guardians or the doctors… If the patient was diagnosed with pneumonia based on the clinical pulmonary infection score (CPIS) during the first 12 hours, they were not included in the study. Number randomised: 80 (gp A: 40; gp B: 40) Number evaluated: 74 (gp A: 39; gp B: 35) Baseline characteristics: ‐Gp A: Age: 14.42 ± 1.39*; M/F: 25/14; APACHE II score: not reported ‐Gp B: Age: 44.61 ± 1.78*; M/F: 25/10; APACHE II score: not reported
Interventions	Comparison: 0.05 ppm ozonated water versus 0.2% CHX Gp A (ozonated water): Both of these mouthwashes were applied identically 3 times a day. Before the intervention, patients’ mouth and trachea received standard suctioning. The swab impregnated with either of the mouthwashes was rubbed rotationally on the upper gums from the right to the left side of the mouth. It was, then, changed and rubbed rotationally on the lower gums from left to right. Two other swabs impregnated with the mouthwash were used to cleanse the upper and lower teeth. After using the swabs and having prepared by the suction, the cuff pressure of the ET tube was increased to 35 mmHg via a manometer specifically used to measure the ET tube cuff pressure. Then, approximately 15 mL of the mouthwash was inserted into the patient’s mouth and 30 seconds later the suctioning process was conducted. Immediately after the intervention, the cuff pressure was reduced to 15 to 20 mmHg. This intervention occurred over a 4‐day period. Gp B (CHX): same as gp A, different mouthwash
Outcomes	1. VAP incidence
Notes	Sample size calculation: to determine the sample size, a pilot study was conducted. By considering α = 0.01, ß = 0.1, P1 = 0.13 and P2 = 0.5, the sample size of each group was estimated as 40. Other information of note: none
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	“a range of numbers was randomly selected by the table of random numbers”.
Allocation concealment (selection bias)	Unclear risk	Not described
Blinding of participants and personnel (performance bias) All outcomes	High risk	Double‐blind means subjects and outcome assessor; blinding of the caregivers not described and not possible. Difference between intervention and control means caregivers would be aware of who was in each group.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	“VAP infection check‐up was carried out by the anaesthesiologist, the only observer blind to the intervention method”.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Although the attrition rate (7.5%) was relatively low, the number of dropouts was unbalanced between groups, and the reason for each dropout was not clearly reported.
Selective reporting (reporting bias)	Low risk	Planned outcomes reported
Other bias	Low risk	No other sources of bias identified