title: Stages of change in physical exercise: a test of stage discrimination and nonlinearity.
abstract: OBJECTIVE
  To investigate the utility of the protection motivation theory (PMT), social-cognitive theory (SCT) and transtheoretical model's (TTM) processes of change (POC) by (1) discriminating between TTM's stages with planned comparisons and (2) examining higher-ordered trends across stages.
  
  
  METHODS
  1582 individuals were included in the analyses that tested severity, vulnerability, response-efficacy, self-efficacy, POC, pros and cons, social and environmental support.
  
  
  RESULTS
  The findings provide evidence for the utility of the PMT and TTM's POC for stage discrimination; stage discontinuity patterns are supported.
  
  
  CONCLUSIONS
  Promotion of health behavior should target stage-specific variables, such as threat appraisals for early stage movements.
authors.affiliation: Psychology, Freie Universitaet Berlin, Habelschwerdter Allee 45 (PF10), 14195 Berlin, Germany. slippke@zedat.fu-berlin.de
authors.forename: Sonia
authors.initials: S
authors.lastname: Lippke
authors.forename: Ronald C
authors.initials: RC
authors.lastname: Plotnikoff
mesh_terms: D000328:Adult; D001364:Awareness; D003430:Cross-Sectional Studies; D015444:Exercise / Q000523:psychology*; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006306:Health Surveys; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D008960:Models, Psychological; D009864:Ontario; D011582:Psychological Theory; D020377:Self Efficacy; D012932:Social Facilitation; D012944:Social Support; D012959:Socioeconomic Factors