Communication and information studies university of Groningen c.j.m.jansen@rug.nl abstraCt Two related studies were performed aimed at finding if and how prior knowledge of threat and efficacy information in a fear appeal message is associated with message outcomes (attitude and behavioural intentions). the extended Parallel Process model (ePPm) (Witte 1992; 1998) served as theoretical framework for one study about a chlamydia fear appeal (n = 57) and another about an alcohol abuse fear appeal (n = 59). Findings from both studies suggest that __________________________________________________________________________________________________ This is an Open Access article distributed under the terms of the Creative Commons Attribution-Non-commercialNo Derivatives Licence (http://creativecommons.org/Licenses/by-nc-nd/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or built upon in any way.
Davis and JansenThis may come as a surprise prior knowledge of threat information is hardly relevant for readers' reactions to a fear appeal message. Prior knowledge of efficacy information, however, proved to play a more important role, most often in a positive way. Findings from both studies furthermore suggest that the ePPm may be incorrect in assuming that individual differences -in this case, in prior knowledge -may only affect fear appeal outcomes in an indirect way, that is through different perceptions of threat and efficacy.