Kendrick 2001.

Methods	Cluster‐randomised controlled trial
Data	Setting: primary care, UK. Families with children aged under 5 years, living in deprived areas; 2393 participants
Comparisons	Investigated the effect of different trial information methods Mailed invitation to participate in an injury prevention trial, including a home safety questionnaire. This was compared to mailed invitation to participate excluding the home safety questionnaire.
Outcomes	Proportion recruited to trial
Notes
Risk of bias
Item	Authors' judgement	Description
Random Sequence generation ok?	Yes	Randomised using ACCESS software by neutral researcher
Allocation concealment?	Yes	See above
Blinding of participants and personnel ok?	Yes	Participants blinded, but researchers know (probably). However, because questionnaire was mailed, there was no way researchers could influence result.
Blinding of outcome assessment ok?	Yes	Objective outcome
Incomplete outcome data handled ok?	Yes	Adequate
Free of selective reporting?	Yes	Recruitment outcome presented, which is all the review needs
Was the study free of other bias?	Yes	No other biases apparent
Overall bias?	No	Low risk of bias