Figure 1From: Semi-automated screening of biomedical citations for systematic reviewsShown are the typical approach and our modified approach that includes semi-automated abstract screening on the left and right-hand, respectively (see text for details). In the modified approach the reviewers train and use a classification model to exclude completely "irrelevant" citations ("Level 1a"). They will trust the model's exclusions, and will review only the citations suggested by the classification model.Back to article page