Traditionally, the literature has analyzed the existence of bias in the evaluation of papers submitted to scientific journals, but it has not considered any possible bias in the evaluation of studies submitted to conferences. In this sense we can ask whether the conferences provide an adequate service for researchers. This study examines whether there is bias in the evaluation of work in progress submitted to a conference, and also examines the explanatory factors of the evaluation. To address these questions we use information from a marketing conference. The results show that completed work receives higher reviewer ratings than work in progress; a bias that is specifically present in the evaluation of information sources, methodology and results. This bias can be explained by the simple fact of being work in progress. Additionally, the results reveal that the number of references from journals listed in the Social Citation Index Report positively influences the evaluation of research studies.