title: Latent interaction effects in the theory of planned behaviour applied to quitting smoking.
abstract: OBJECTIVE
  This study applies three latent interaction models in the theory of planned behaviour (TPB; Ajzen, 1988, Attitudes, personality, and behavior. Homewood, IL: Dorsey Press; Ajzen, 1991, Organ. Behav. Hum. Decis. Process., 50, 179) to quitting smoking: (1) attitude × perceived behavioural control on intention; (2) subjective norms (SN) × attitude on intention; and (3) perceived behavioural control × intention on quitting behaviour.
  
  
  METHODS
  The data derive from a longitudinal Internet survey of 939 smokers aged 15-74 over a period of 4 months. Latent interaction effects were estimated using the double-mean-centred unconstrained approach (Lin et al., 2010, Struct. Equ. Modeling, 17, 374) in LISREL.
  
  
  RESULTS
  Attitude × SN and attitude × perceived behavioural control both showed a significant interaction effect on intention. No significant interaction effect was found for perceived behavioural control × intention on quitting.
  
  
  CONCLUSIONS
  The latent interaction approach is a useful method for investigating specific conditions between TPB components in the context of quitting behaviour. Theoretical and practical implications of the results are discussed.
authors: The Norwegian Center for Child Behavioural Development, Oslo, Norway.
authors: Silje Sommer
authors: SS
authors: Hukkelberg
authors: Knut A
authors: KA
authors: Hagtvet
authors: Velibor Bobo
authors: VB
authors: Kovac
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D033182:Intention; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D011582:Psychological Theory; D012907:Smoking / Q000523:psychology*; D016540:Smoking Cessation / Q000523:psychology*; D011795:Surveys and Questionnaires; D055815:Young Adult