Factors influencing the perceived credibility of diet-nutrition information web sites

Highlights

• Dual-processing models explain the processing of online diet-nutrition information.

• Message accuracy has a greater effect on website credibility than source expertise.

• Prior knowledge moderates message and source cue effects on website credibility.

• Issue involvement matters with web site credibility when the message is accurate.

Abstract

This study investigated the factors that influence the perceived credibility of web sites providing diet and nutrition information. Undergirded by the dual-processing models (i.e., Elaboration Likelihood Model and Heuristic Systematic Model), an online experiment (N = 575) was conducted to examine how perceptions of online diet and nutrition information credibility are influenced by source expertise cues and message accuracy; the effects of prior knowledge and interest in the information also were assessed. Results showed that message accuracy increased perceived credibility of the web site regardless of the level of source expertise. However, source expertise had an important effect on website credibility perceptions among those who exhibited low prior knowledge. Finally, message accuracy had a greater impact on web site credibility among those who were highly involved in the issue compared to those who were less involved. The findings increase our understanding of the factors that impact individuals’ processing of online diet and nutrition information and suggest elements practitioners should consider including to create the most effective online sources for diet and nutrition information.

Introduction

With the advent of new technology, people are now paying more attention to science-based health information (Thomm & Bromme, 2012). In particular, many people are concerned about diet and nutrition information because the United States is in the midst of what the Centers for Disease Control have called an “obesity epidemic” (Centers for Disease Control, 2011). Because obesity can cause life-threatening diseases, it is regarded as a major problem, typically associated with poor dietary habits (Malik, Willett, & Hu, 2013). Controlling one's dietary habits and caloric intake should be the first move to avoid weight gain and lower the risk of developing obesity-related diseases such as diabetes and cancer. However, Crow (2012) has suggested that one reason many Americans are overweight is that they do not understand what constitutes a healthy diet. Thus, people need access to appropriate diet and nutrition information, which could help diminish the obesity epidemic.

In today's society, the Internet plays a significant role in heath information seeking among the public. The Pew Internet and American Life Project survey revealed that, in 2013, 72% of American Internet users had searched for health information online (Fox & Duggan, 2013). These numbers suggest that the convenience of accessing online information supersedes visiting a doctor in terms of satisfying people's desire to obtain information about their health problems. Therefore, the Internet can help users gather health information by providing consumers with useful knowledge about health-related issues (Wang, Wang, Wang, Liang, & Xu, 2012).

However, people are sometimes confused by the information they find online, simply because of the overwhelming volume of data the Internet provides (Goldberg & Sliwa, 2011; Theodosiou & Green, 2003). The volume of information, including often conflicting information, can cause people to wonder whether the information they find online is indeed correct. Consumers' perception of the credibility of online information plays a key role in determining which websites they find useful (Lim & Van Der Heide, 2015). Previous studies have suggested that credibility significant influences users’ perceptions of health-related messages and their behavioral responses to those messages (e.g., Harris et al., 2009, Hu and Sundar, 2010). If health professionals and organizations hope to harness public use of online information as a tool in reducing the rates of overweight and obesity, they need to understand how individuals decide which online information to trust in making decisions about their diet. Although a few studies have investigated participation in online nutrition-related interventions (Colleran & Lovelady, 2012; Robroek, Brouwer, Lindeboom, Oenema, & Burdorf, 2010; Robroek, Lindeboom, & Burdorf, 2012; Thorndike et al., 2012), the relationship of credibility with message features and source cues has not been investigated comprehensively (Hong, 2006). To help fill this gap in online health communication research, this study investigated the impact of two key factors that may influence how people determine the credibility of online health information. Specifically, the present study investigated diet/nutrition information credibility through the lens of the dual-processing models; the purpose was to determine how source expertise and message accuracy affect information credibility in online media platforms.