What makes information in online consumer reviews diagnostic over time? The role of review relevancy, factuality, currency, source credibility and ranking score

Online consumer reviews (OCRs) have become one of the most helpful and influential information in consumers purchase decisions. However, the proliferation of OCRs has made it difficult for consumers to orientate themselves with the wealth of reviews available. Therefore, it is paramount for online organizations to understand the determinants of perceived information diagnosticity in OCRs. In this study, we investigate consumer perceptions and we adopt the Elaboration Likelihood Model to analyze the influence of central (long, relevant, current, and factual OCRs) and peripheral cues (source credibility, overall ranking scores) on perceived information diagnosticity (PID). We consider the potential moderating effect of consumer involvement, and tested the robustness of the theoretical framework across time. Based on two surveys carried out in 2011 and in 2016, this study demonstrates the dynamic nature of the antecedents of PID in e-WOM. We found that long reviews are not perceived as helpful, while relevant and current reviews as well as overall ranking scores are perceived as diagnostic information in both samples. The significance of the predicting power of review factuality and source credibility has evolved over time. Both central (review quality dimensions) and peripheral cues (ranking score) were found to influence PID in high-involvement decisions. (C) 2017 Elsevier Ltd. All rights reserved.