In psychology,the theory of planned behavior is a theory about the link between attitudes and behavior.It was proposed by Icek Ajzen (last name sometimes spelled 'Aizen') as an extension of the theory of reasoned action.It is one of the most predictive persuasion theories.It has been applied to studies of the relations among beliefs,attitudes,behavioral intentions and behaviors in various fields such as advertising,public relations,advertising campaigns,healthcare,etc.