Lima 2008.

Methods	Trial design: 2‐armed, single‐blind, active‐controlled RCT Location: Brazil Number of centres: single public day nursery, São Luis Recruitment period: study commenced in/before 2006
Participants	Inclusion criteria: low‐income public nursery attendees Exclusion criteria: not reported Baseline caries: 5.1 "cavities" (Gps A + B caries inactive; Gp C: 2.5 ANC (SD 1.5); Gp D: 5.3 ANC (SD 6.5)). Baseline characteristic (caries status) "balanced" (evaluated participants only) Age at baseline (years): range 2 to 4 years, mean 3.3 years (Gp A: 3.3 years; Gp B 3.2 years; Gp C: 3.4 years; Gp D: 3.2 years). Baseline characteristic (age) "balanced" (evaluated participants only) Sex: Gp A: 13 F:11 M; Gp B: 10 F:13 M; Gp C: 10 F:12 M; Gp D: 8 F:13 M). Baseline characteristic (sex) "balanced" (evaluated participants only) Any other details of important prognostic factors: background exposure to fluoride in community water supply < 0.3 ppm F Number randomised: 120 (Gp A: 30; Gp B: 30; Gp C: 30; Gp D: 30) Number evaluated: 90 at 1 year (present at final assessment. Gp A: 24; Gp B: 23; Gp C: 22; Gp D: 21) Attrition: 25% dropout rate after 1 year (study duration = 1 year). Reasons for attrition: moved away from study area, children leaving nursery setting; no differential group losses
Interventions	Comparison: FT versus FT Gp A (n = 30): 500 ppm NaF; caries‐inactive participants; abrasive system: none reported; school use/supervised daily frequency; home use/unsupervised, daily frequency assumed Gp B (n = 30): 1100 ppm NaF; caries‐inactive participants; abrasive system: none reported; school use/supervised daily frequency; home use/unsupervised, daily frequency assumed Gp C (n = 30): 500 ppm NaF; caries‐active participants; abrasive system: none reported; school use/supervised daily frequency; home use/unsupervised, daily frequency assumed Gp D (n = 30): 1100 ppm NaF; caries‐active participants; abrasive system: none reported; school use/supervised daily frequency; home use/unsupervised, daily frequency assumed
Outcomes	Primary: number of lesions becoming active/cavities or inactive by initial caries status (at 1 year) Secondary: none assessed Assessments irrelevant to this review's scope: n/a Follow‐up duration: 1 year
Notes	Adverse effects: not reported Funding source: materials provided by manufacturer (Colgate‐Palmolive) and funding obtained from CNPq (Brazilian National Council for Scientific and Technological Development) Declarations/conflicts of interest: institutional affiliations reported only Data handling by review authors: caries‐inactive and caries‐active groups analysed separately Other information of note: clinical caries assessment by single examiner; intra‐examiner agreement assessed by second clinical exam in 10% of the sample after 15 days (Kappa 0.95)
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: ".. randomised single‐blind clinical trial"
Allocation concealment (selection bias)	Unclear risk	Comment: insufficient information
Blinding (performance bias and detection bias) All outcomes	Low risk	Quotes: ".. randomised single‐blind clinical trial" and "The study was blinded only for the examiner..." Comment: examiner was blinded to the treatment allocation
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: reasons for attrition stated. Attrition rate was moderate after 1 year, 25% overall and similar in both toothpaste groups and unlikely to be related to intervention
Selective reporting (reporting bias)	Low risk	Comment: all pre‐specified outcomes reported (progression and arresting of lesions by toothpaste group and inital caries status)
Baseline characteristics balanced?	High risk	Comment: more males in 1100 ppm F group than females (26:18 versus 23:23), lower mean activated non‐cavitated caries lesions in 500 ppm F group (2.5 (1.5 SD) versus 5.3 (6.5 SD))
Free of contamination/co‐intervention?	Unclear risk	Comment: possible contamination in school brushing sessions but unlikely under supervision. Possible contamination at home brushing