Citations remain a prime, yet controversial, measure of academic performance. Ideally, how often a paper is cited should solely depend on the quality of the science reported therein. However, non-scientific factors, including structural elements (e.g., length of abstract, number of references) or attributes of authors (e.g., prestige and gender), may all influence citation outcomes. Knowing the predicted effect of these features on citations might make it possible to 'game the system' of citation counts when writing a paper. We conducted a meta-analysis to build a quantitative understanding of the effect of similar non-scientific features on the impact of scientific articles in terms of citations. We showed that article length, number of au...