Takeuchi 1968.
| Methods | Trial design: 2‐armed, double‐blind, placebo‐controlled, stratified RCT Location: Japan Number of centres: 1 Recruitment period: study began 1964 | |
| Participants | Inclusion criteria: unknown Exclusion criteria: unknown Baseline caries: reported at surface level only (Gp A: 121/3175 (3.8%) surfaces affected; Gp B: 111/3362 (3.3%) surfaces affected) Age at baseline (years): range 8 to 10 years (Gp A: range 8 to 10 years; Gp B: range 8 to 10 years) Sex: unknown Any other details of important prognostic factors: background exposure to fluoride: not reported Number randomised: 1230 (Gp A: 611; Gp B: 619) Number evaluated: 620 at 1 year (available at final examination) (total and group distribution unknown, data reported at a surface level) Attrition: 50% dropout after 3 years (study duration = 1 year) | |
| Interventions | Comparison: FT versus PL Gp A (n = 611): SMFP 1000 ppm F; abrasive system: not reported; home use (unsupervised) with periodical brushing management by school teacher Gp B (n = 619): placebo; abrasive system: not reported; home use (unsupervised) with periodical brushing management by school teacher | |
| Outcomes | Primary: newly developed caries surfaces ‐ (CA) cl + DR (xr); caries onset rate (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: not reported Declarations/conflicts of interest: institutional affiliations reported only Data handling by review authors: not included in meta‐analysis Other information of note: clinical (VT) and radiographic (DR) caries assessment by 2 examiners according to WHO criteria, diagnostic threshold = CA | |
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Unclear risk | Quote: "By stratified random sampling in various degrees of caries ...." Comment: random sequence generation |
| Allocation concealment (selection bias) | Unclear risk | No information provided |
| Blinding (performance bias and detection bias) All outcomes | Unclear risk | No information provided |
| Incomplete outcome data (attrition bias) All outcomes | High risk | Comment: overall dropout not calculable, as number of children present at final examination not reported |
| Selective reporting (reporting bias) | High risk | Outcomes reported: DMFS increment ‐ (CA) cl (DR) xr, reported at 12 month follow‐up caries rate numerical data reported at surface level only Comment: trial protocol not available. All outcomes listed in Methods section were reported (DFS) |
| Baseline characteristics balanced? | Low risk | Prognostic factors reported: caries Comment: baseline DMFS appears balanced |
| Free of contamination/co‐intervention? | Unclear risk | No information provided |