Provocative messages targeting childhood obesity are a central means to increase problem awareness . But what happens when different online media platforms take up the campaign comment re contextualize and evaluate it Relating to preliminary findings of persuasion research we postulate that source credibility perceptions vary across types of online media platforms and contextualization of the message . Individual characteristics in particular weight related factors are assumed to influence message effects . A 3 2 experimental design with students aged between 13 and 18 years was conducted . Results show an interaction between media type and argumentation for affective self perceptions of weight . Self relevance varies based on different source credibility perceptions . Overall campaign re contextualization of provocative messages may result in negative persuasion effects and needs to be considered in campaign development . Childhood anti obesity campaigns are often designed in a highly provocative way in order to increase attention . Social media platforms are a prominent online environment to spread such health related public service announcements raise awareness and motivate discussion . However when applying this strategy public healthcare runs the risk of losing control over the effects of its campaigns . Follow up communication in different media platforms such as blogs online news sites or social networking sites takes up the campaign comments re contextualizes and evaluates it . On the one hand this strengthens the attention focused on the campaign on the other hand the question emerges how different context formats affect campaign perceptions . Even if the core messages of the campaigns are still equal variations in the argumentative contextualization and the media platform change the representation of the message or in other words the frame of the message . In terms of how campaigns are embedded two aspects stand out . First the contextualization of the content could either reinforce the argumentation of the campaign or impair its original message . The arguments of the original message are either supported or rejected which resembles value framing in political communication . Second follow up communication regarding the campaigns could be placed on different online media platforms reaching from more traditional journalistic contexts such as online newspapers to social media environments such as Facebook or blogs . Both re contextualization factors address the credibility and trustworthiness of the context the message and of the communicator . However research has failed to analyze the comparative effects of social campaigns in these different online media environments . A highly relevant example in regard to such concerns is the perception of obesity related health messages especially when these campaigns address children and adolescents since such campaigns are increasingly at risk of offending and stigmatizing children affected by obesity . However there is little research on the effects of campaigns against childhood obesity and the fact that they convey negative or even shocking messages in online media . Considering the lack of research on this subject our study aims to close the gap and investigate the effects of different. 


Summary: First systematic research on variations of online source credibility perceptions. Experimental study on online re contextualization effects. Stratified sample for education levels of 700 secondary school students. Provocative campaigning takes the risk of boomerang effects. Media and argumentation type affects affective self perceptions of weight.