Hargreaves 1973.

Methods	Quasi‐random allocation; double‐blind (A); placebo‐controlled; 4% drop out after 3 years (study duration = 3 years). Reasons for attrition NR; exclusions based on presence in all follow‐up examinations; any differential group losses not assessable.
Participants	303 children analysed at 3 years (present for all examinations). Age at start: 6 years. Surfaces affected at start: 13.9 dfs (data for deciduous dentition only). Background exposure to fluoride: none reported. Year study began: 1968. Location: UK.
Interventions	FT versus PL (SMFP group = 2400 ppm F). Home use/unsupervised, daily frequency assumed. Abrasive system: Al oxide trihydrate.
Outcomes	1‐3yNetDFS increment ‐ (E+U)(CA)cl+(ER)xr. Reported at 3 years follow up. DFT. DMFS. DMFT. ECSI.
Notes	Participants randomised (N = 316); numbers by group NR. Baseline characteristics (age, tar, dfs, dmfs, dft, dmft, ecsi) 'balanced' (no DFS data at start). Clinical (VT) caries assessment by two examiners; diagnostic threshold = CA; radiographic assessment (2 postBW) by two examiners; diagnostic threshold = ER. State of tooth eruption included = E/U. Diagnostic errors NR.
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment (selection bias)	High risk	C ‐ Inadequate