The effect of product review balance and volume on online Shoppers' risk perception and purchase intention

•Our study validates some findings in econometric studies pertaining to review balance and volume, with some differences regarding the effects of review volume.•Our study enriches researchers' understanding of risk perception and uncertainty in e-commerce.•Our study reveals that the relationship between perceived uncertainty and purchase intention becomes insignificant in the presence of attitude toward purchasing.•Our study explains the success of the strategy of having manipulated reviews.

Online reviews are viewed as an important source of information enabling online shoppers to assess the quality of products/services. An important function of reviews is to reduce the risk and uncertainty that online buyers perceive relating to the product purchase. There are many aspects of reviews that may influence risk perception. This study examines the effect of social consensus in product reviews, represented by review balance and volume, on online shoppers' risk perception, uncertainty, attitude and subsequent purchase intention, using a quasi-experimental design and online questionnaires. Results show that the four proposed risk concerns are good predictors of online shoppers' overall risk in e-commerce; perceived risk is a major determinant of online shoppers' attitude toward purchasing, which in turn determines their purchase intention. However, no significant causal effect between perceived uncertainty and purchase intention was found.