De Visschere 2012.

Methods	Cluster‐randomised controlled trial, 2 arms Study period: spring to winter 2009 Planned follow‐up period: 6 months
Participants	Country: Belgium (Flanders) Setting: 12 nursing homes (with somatic and psychogeriatric residents) Target audience for the intervention: nursing home staff Number of randomised participants (nursing home residents; nursing staff): 373; 760 Number of analysed participants (nursing home residents; nursing staff): 297; 259 Age, mean, years (SD): 84.5 (8.5) in IG, 84.9 (7.6) in CG Female: 68.4% in IG, 78.0% in CG Edentulous residents: 55% in IG, 54.3% in CG Residents with dental prosthesis: 72.3% in IG, 69.1% in CG Inclusion criteria: having teeth and/or (removable) partial or complete dentures; physically suitable for examination; expected to be residing in the care home during the entire 6‐month period Exclusion criteria: residents in day care, in short‐term residency, in coma, in palliative care or terminally ill, using a denture adhesive, expressing verbal or physical resistiveness before or during an oral examination
Interventions	Intervention group Supervised implementation of the "Oral health care Guideline for Older people in Long‐term care Institutions (OGOLI)" including multiple components: Education/skills training: oral presentation (1.5 hours) for the managing director, care home study supervisor, the ward heads, and the ward oral healthcare organiser (WOO) about OGOLI, daily oral healthcare protocol, and the supervised implementation project lecture (2 hours) for the WOOs including theoretical and practical essentials of OGOLI and the daily oral healthcare protocol practical education (1 hour) for the WOOs according to the train‐the‐trainer concept theoretical and practical education session (1.5 hour) for all nurses and nurse assistants at ward level, presented by the ward’s WOO using all education materials. WOOs presented a summary of OGOLI and all executive actions (e.g. tooth brushing) were taught and demonstrated with ward residents on site Information material: PowerPoint presentation, OGOLI, daily oral healthcare protocol Additional components: WOO encouraged and assisted nursing staff in the daily delivery of oral health care monitoring visits of a dental hygienist together with an investigator (every 6 weeks including WOOs support and where necessary repeating educational sessions for (new) nursing staff) daily oral healthcare protocol Control group Usual oral health care according to the no‐supervised implemented guideline (since 2007 Dutch guideline OGOLI) The intervention was implemented in the control nursing homes after completion of data collection. Co‐interventions (for the intervention group) oral healthcare material and products
Outcomes	Primary outcomes Oral hygiene measures were assessed at baseline and 6 months after the start of the study. Dental plaque: Plaque Index by Silness 1964 Denture plaque: method of Augsburger 1982 Tongue coating: Tongue Coating Index (Winkel 2003) Oral health‐related knowledge and attitude were assessed at baseline and 6 months after the start of the study. (nursing staff) knowledge: self administered questionnaire (15 statements assessing knowledge of oral pathology and oral hygiene) (nursing staff) attitude: self administered questionnaire (4 statements)
Funding	Research project is funded by Open Ankh, Soest and Stichting De Opbouw, Utrecht, the Netherlands. Oral healthcare products were provided free by GABA International, Eureka Pharma Belgium, Oral‐B Belgium, and Johnson & Johnson consumer S.A/N.V.
Notes	Questionnaire (included 3 parts: personal items, attitude statements, knowledge statements): The reliability of the attitude part of the questionnaire was measured by a test–retest procedure in a comparable nursing home not involved in the study. Content and construct validity (knowledge part) was assessed by experts in the field of gerodontology including 1 dental hygienist and 3 dentists.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "randomly allocated to the intervention (n = 6) or the control group (n = 6) using computer‐aided tools"
Allocation concealment (selection bias)	Unclear risk	Insufficient information
Blinding of participants and personnel (performance bias) All outcomes	Low risk	No blinding of participants and personnel or incomplete blinding, but the review authors judge that the assessed outcomes are not likely to be influenced by lack of blinding.
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "The examiners were masked, they did not know whether a nursing home was allocated to the intervention or the control group."
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote (De Visschere, clinical measures of nursing home residents): "main reasons for loss to follow‐up: death (35%), administrative errors (30%), address change, move or absence (15%), hospitalisation or sickness (9%) or refusals (9%). There were no differences in loss to follow‐up between those randomised to the intervention group and to the control group." Quote (Janssens, knowledge of nursing staff): baseline N = 760; "259 (34%) respondents were found, 165 belonging to the intervention group and 94 to the control group." "All respondents were analysed in the groups to which they were originally allocated (intention to treat analysis). There were no significant differences between the respondents (n = 259) and non‐respondents (n = 392) for the explanatory and outcome variables."
Selective reporting (reporting bias)	High risk	Outcomes reported as planned in the study protocol. Tongue coating as outcome not preplanned.
Other bias	Low risk	None apparent