Stages of change in physical exercise: a test of stage discrimination and nonlinearity.
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.
Lippke
Sonia
S
Psychology, Freie Universitaet Berlin, Habelschwerdter Allee 45 (PF10), 14195 Berlin, Germany. slippke@zedat.fu-berlin.de
Plotnikoff
Ronald C
RC
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