Fogels 1988.
| Methods | Trial design: 2‐armed, double‐blind, active‐controlled and stratified RCT Location: USA Number of centres: 23 parochial schools in greater Boston area, Massachusetts Recruitment period: study commenced 1981 | |
| Participants | Inclusion criteria: not reported Exclusion criteria: not reported Baseline caries: 3.7 DMFS (Gp A: 3.85 (SD 3.92); Gp B: 3.55 (SD 3.74)); 2.3 DMFT (Gp A: 2.36 (SD 2.06); Gp B: 2.23 (SD 2.03)). Baseline characteristics (DMFS, DMFT, sound surfaces) "balanced" (from 3 year follow‐up attendees) Age at baseline (years): range 6 to 11 years, mean 9 years (Gp A: 9.36 years (SD 1.05); Gp B: 9.40 years (SD 1.09)). Baseline characteristic (age) "balanced" (from 3 year follow‐up attendees) Sex: 1041 F:872 M (Gp A: 502 F:448 M; Gp B: 539 F:424 M). Baseline characteristic (sex) "balanced" (from 3 year follow‐up attendees) Any other details of important prognostic factors: background exposure to fluoride in community water supply 1.0 ppm F Number randomised: 2411 (Gp A: 1200; Gp B: 1211) Number evaluated: 1913 at 3 years (present at final assessment. Gp A: 950; Gp B: 963) Attrition: 20.7% dropout (for all study groups combined) after 3 years. Reasons for attrition: withdrawal from the study or absent from final examination; no differential group losses | |
| Interventions | Comparison: FT versus FT Gp A (n = 1200): SMFP 1000 ppm F; silica abrasive system; home use/supervised brushing at school, daily frequency assumed Gp B (n = 1211): SMFP 1500 ppm F; silica abrasive system; home use/supervised brushing at school, daily frequency assumed | |
| Outcomes | Primary: 3‐year DMFS increment cl + xr; DMFT increment; proportion developing caries (at 3 years) Secondary: adverse effects Assessments irrelevant to this review's scope: none Follow‐up duration: 3 years | |
| Notes | Adverse effects: "no adverse experiences related to the dentifrices were observed throughout the course of this trial" Funding source: not reported Declarations/conflicts of interest: 2 of 5 authors employed by the product manufacturer (Lever Brothers Co, Edgewater, NJ, USA: Robert Miragliuolo and Lewis P Cancro) Data handling by review authors: n/a Other information of note: 18.8% of children had orthodontic treatment, with banded teeth excluded from the analysis and 8.4% were given sealants. 1 trained and calibrated examiner used. 10% of children randomly re‐examined to assess consistency of scoring: decayed surfaces 84.7% to 88.9% consistent, filled surfaces 95.1% to 98.8% consistent | |
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Unclear risk | Quote: "... subjects were stratified according to age and sex and were randomly assigned to one of two fluoride dentifrices" |
| Allocation concealment (selection bias) | Unclear risk | Comment: insufficient information |
| Blinding (performance bias and detection bias) All outcomes | Low risk | Quote: "...double‐blind study" |
| Incomplete outcome data (attrition bias) All outcomes | Unclear risk | Comment: attrition rate was moderate after 3 years, 21% and 21% in 1000, 1500 groups Quote: "The dropouts either withdrew from the study during the course of the trial or were absent at the third year clinical or radiographic examination" Comment: not given for each group separately |
| Selective reporting (reporting bias) | Low risk | Comment: results reported DMFT, DMFS, per cent caries free at 3 years |
| Baseline characteristics balanced? | Low risk | Comment: balance of sex, age and caries disease at baseline comparable |
| Free of contamination/co‐intervention? | Unclear risk | Comment: possible in school brushing sessions A proportion of the subjects were fitted with sealants during the course of the study and this proportion was higher (9.6% as opposed to 7.2%) in the higher fluoride group which showed a lower caries increment |