title: Home-based smoking prevention program Smoke-free Kids on smoking-related cognitions: Secondary outcomes from a cluster randomized controlled trial.
abstract: OBJECTIVE
  The home-based smoking prevention programme 'Smoke-free Kids' did not have an effect on primary outcome smoking initiation. A possible explanation may be that the programme has a delayed effect. The aim of this study was to evaluate the effects on the development of important precursors of smoking: smoking-related cognitions.
  
  
  METHODS
  We used a cluster randomised controlled trial in 9- to 11-year-old children and their mothers. The intervention condition received five activity modules, including a communication sheet for mothers, by mail at four-week intervals. The control condition received a fact-based programme. Secondary outcomes were attitudes, self-efficacy and social norms. Latent growth curves analyses were used to calculate the development of cognitions over time. Subsequently, path modelling was used to estimate the programme effects on the initial level and growth of each cognition.
  
  
  RESULTS
  Analyses were performed on 1398 never-smoking children at baseline. Results showed that for children in the intervention condition, perceived maternal norms increased less strongly as compared to the control condition (β = -.10, p = .03). No effects were found for the other cognitions.
  
  
  CONCLUSIONS
  Based on the limited effects, we do not assume that the programme will have a delayed effect on smoking behaviour later during adolescence.
authors.affiliation: a Research Centre for Adolescent Development, University Utrecht , Utrecht , The Netherlands.
authors.forename: Marieke
authors.initials: M
authors.lastname: Hiemstra
authors.affiliation: b Behavioural Science Institute, Radboud University Nijmegen , Nijmegen , The Netherlands.|c Trimbos Institute , Utrecht , The Netherlands.
authors.forename: Rutger C M E
authors.initials: RC
authors.lastname: Engels
authors.affiliation: d Department of General Practice , Maastricht University , Maastricht , The Netherlands.
authors.forename: Onno C P
authors.initials: OC
authors.lastname: van Schayck
authors.affiliation: b Behavioural Science Institute, Radboud University Nijmegen , Nijmegen , The Netherlands.|c Trimbos Institute , Utrecht , The Netherlands.
authors.forename: Roy
authors.initials: R
authors.lastname: Otten
mesh_terms: D001290:Attitude; D002648:Child; D016000:Cluster Analysis; D003071:Cognition; D005260:Female; D006801:Humans; D008297:Male; D009035:Mothers / Q000523:psychology; D015397:Program Evaluation; D020377:Self Efficacy; D012907:Smoking / Q000523:psychology*; D000074606:Smoking Prevention; D066262:Social Norms
keywords: children; cluster randomised controlled trial; cognitions; home-based; prevention