Shenoy 2010

Methods	Study design: cross‐over controlled before‐and‐after study Conducted in: India Unit of randomisation: not applicable Unit of analysis: school Setting: Mangalore City, Karnataka State, South Western coast of the Indian Peninsula Funded by: Study declared source of support as "Nil" Duration of the study: 36 weeks
Participants	Inclusion criteria Schools: consent to participate in the study provided by school authorities, no past dental health education programme, children from all social classes from 1 to 5 with ≥ 50 children 12 to 13 years of age Children: Socioeconomic status of participants' parents was evaluated, and children of socioeconomic classes 1 and 5 were selected. Children had to be 12 to 13 years old and had to have intact permanent teeth and good general health Exclusion criteria Children: presence of oral mucosal lesions, intake of medications affecting oral health (antibiotics, mouthwashes) in the 2 weeks leading up to the study and before each examination, presence of crowding/overlapping of teeth resulting in severe gingival inflammation, children undergoing orthodontic treatment and children requiring any emergency dental treatment Age at baseline: children 12 to 13 years of age Total at baseline: 450 Total at 36‐week analysis: 415 N (controls baseline): 280 N (controls follow‐up): 262 N (interventions baseline): 170 N (interventions follow‐up): 153 Recruitment: through schools via convenience sampling Gender: not reported
Interventions	Intervention School Dental Health Education programme. Twenty‐minute session using audiovisual aids on effects of diet on teeth, prevention of oral health disease, interaction between oral health and general health and benefits of regular brushing using proper techniques Control: no intervention Duration of intervention: Sessions were delivered every 3 weeks
Outcomes	Gingival index Plaque index
Implementation related factors	Theoretical basis: not reported Resources for implementation: Dental Health Education programme materials including audiovisual aids, slide projector, dentoform model, charts, photo albums, posters and plaster models, training materials and educator (unclear from the article who administered DHE14) Who delivered the intervention: unclear PROGRESS categories assessed at baseline: SES, education PROGRESS categories analysed at outcome: not reported Outcomes related to harms/unintended effects: not reported Intervention included strategies to address diversity or disadvantage: Only children from socioeconomic classes 1 and 5 were included in the study Economic evaluation: not reported
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Schools were not randomly allocated. Study authors used convenience sampling to select children
Allocation concealment (selection bias)	High risk	Schools and participants were selected on the basis of inclusion/exclusion criteria
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Unclear
Selective reporting (reporting bias)	Low risk	Published report presents all expected outcomes of interest to the review
Other bias	Unclear risk	Unclear
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Two schools from each social class were taken as controls to prevent ‘contamination’ of the programme within schools caused by children talking to each other
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Unclear