McFall 1993.

Methods	Setting: community, USA Recruitment: during a TV cessation programme
Participants	Smokers who registered and received the manual or reported viewing at least 1 part of the programme
Interventions	∙ TV programme and ALA FfS ∙ Maintenance; first bullet above and 10 newsletters over following 6 months
Outcomes	Abstinence at 12 months (24 months' data reported but point prevalence with increase over time, so does not represent a more conservative measure; RR similar) Validation: none
Notes	2 vs 1, effect of additional materials
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Randomised; method not described
Allocation concealment (selection bias)	Unclear risk	No details given
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Unclear if participants were aware of what other participants were receiving; no biochemical validation; maintenance group has more communication than control group
Incomplete outcome data (attrition bias) All outcomes	Low risk	24% lost in maintenance condition, 27% in control condition Meta‐analysis includes responders; including losses would yield a less conservative effect