48 randomized, placebo-controlled trials were analyzed to determine the proportion of studies evaluating hyaluronic acid efficacy in knee osteoarthritis sponsored by industry, and if the presence of a financial conflict of interest of an author was associated with the qualitative conclusions of the study. The results of the review indicated that at least over half (62.5%) of the studies were industry funded, and that there was a significant correlation between the conclusions of a study and the reporting of a financial conflict of interest for at least one of the authors.