Roca Biosca 2011.

Study characteristics
Methods	Study design: Single‐blind RCT Location: Tarragona, Spain Number of centres: 1 Study period: June 2006 to May 2009 Funding source: Grant from Health Investigation Fund (FISS 06/060)
Participants	Setting: ICU (14‐bed) Inclusion criteria: adults aged > 18 years, requiring mechanical ventilation for at least 48 hours, no pneumonia at baseline, at least 2 premolars and 1 incisor, consenting to take part Exclusion criteria: edentulous, suspected pneumonia < 18 years, requiring < 48 hours mechanical ventilation, tracheotomy, moribund (death expected within 72 hours) allergic to chlorhexidine Number randomised: 147 Number evaluated: not stated Baseline characteristics: report stated that there were no differences in gender, age, diagnosis, APACHE scores between the groups at baseline. No supporting data reported
Interventions	Comparison: powered toothbrush + standard oral care vs standard oral care alone Experimental group: Standard oral hygiene protocol + powered toothbrush. Participant was elevated to 35°, oropharyngeal secretions were aspirated, intubation cuff pressure checked, then teeth, tongue and oral cavity cleaned with swab soaked in 10 mL 0.12% chlorhexidine digluconate. Solution left for 30 seconds then excess was aspirated. All tooth surfaces then brushed using a powered toothbrush Control group: Standard oral hygiene protocol alone as described for treatment group
Outcomes	4 outcome variables planned: 1. Plaque index (Silness 1964) days 1, 5 and 10 2. Plaque cultures 3. VAP 4. Halitosis
Notes	Sample size calculation: not reported Translated from Portuguese by Luisa Fernandez‐Mauleffinch Email to authors sent 14 November 2012
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	"Group assignment was done randomly by sealed envelope". Method of sequence generation not described
Allocation concealment (selection bias)	Low risk	"Group assignment was done randomly by sealed envelope".
Blinding of participants and personnel (performance bias) All outcomes	High risk	Not possible to blind participants or personnel
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Study described as single blind but unclear who was blinded
Incomplete outcome data (attrition bias) All outcomes	High risk	Numbers of participants included in outcome of plaque index were 74 and 73 at day 0, 60 and 57 at day 5, and 29 and 32 at day 10 for toothbrush and control groups respectively. Reasons for missing outcome data are extubation, need for tracheotomy, VAP, death or intubation for total of 28 days. No information as to numbers missing by group for each reason
Selective reporting (reporting bias)	High risk	Planned outcomes of plaque index and microbiological culture reported, but data for VAP and halitosis in each group not reported
Other bias	Unclear risk	Insufficient information in trial report to be clear about potential for other bias