Describe the transtheoretical model of behavior change,and briefly describe each stage.

The transtheoretical model was developed to account for individual differences in the course of changing health behaviors.According to this model,people can be classified as being in one of five stages with respect to making a particular health behavior change: precontemplation,contemplation,preparation,action,or maintenance.
I.Precontemplation-During this stage,people express no intention to change the health behavior.
II.Contemplation-During this stage,people are aware that they should change their behavior and are seriously contemplating doing so.
III.Preparation-People in the preparation stage are ready to make a health change and intend to do so within the next month.
IV.Action-During the action stage,people are successfully modifying their health behavior.
V.Maintenance-After six months of successful behavior change during the action stage,people are considered having entered the maintenance stage.At this point,they continue to work to maintain the health behavior change they have made.