Kotch 1989 USA.

Methods	Cluster‐RCT Allocation sequence: unclear Allocation concealment unclear Blinding: participants and assessors blinded Inclusion of participants in the analysis: unclear Length of follow‐up: 7 months Cluster‐adjustment method: adjusted
Participants	Number: 24 day‐care centres, with 389 classrooms Inclusion criteria: children < 3 years; present in the day care at least 20 hour per week; absence of chronic illness or medication that would predispose to infection; youngest of potentially eligible children in the same family; consenting English‐speaking parents with access a telephone; intending to remain in day‐care centre throughout trial Exclusion criteria: not stated Age: < 3 years
Interventions	Intervention (see Table 5 for detailed description): Large group training Curriculum for caregivers Control: No intervention
Outcomes	Diarrhoeal rates
Notes	Location: Cumberland County, North Carolina, USA Duration: October 1988 to May 1989
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not described.
Allocation concealment (selection bias)	Unclear risk	Not described.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	" specifically, parental illness reports were blind to the intervention status of their children's DCCs, potential confounders were controlled for and effect modifiers were examined".
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Assessors were blinded.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	18 children dropped, 1 day care centre withdrew from the trial.
Selective reporting (reporting bias)	Unclear risk	Unclear.
Other bias	Unclear risk	Unclear