Publication bias

Yet other biases in research emerge during the dissemination of results. 

Publication bias refers to the selective reporting of positive (often significant and desirable) results in the scientific literature. Publication bias emerges when researchers fail to publish non-significant or otherwise negative results, either because they feel that such results are not interesting or because (they believe that) peer reviewers or editors might not be welcoming to such results. Publication bias creates false impression on the robustness of findings in the literature and in systematic reviews and meta-analyses based on the literature.