Objective: Trauma, with resultant bleeding, is a significant cause of morbidity and mortality throughout the world, however the best possible method of bleeding control by immediate responders is unknown. We performed a systematic review of the effectiveness of treatment modalities for severe, life-threatening external bleeding in the out-of-hospital first aid setting. Methods: We followed the Cochrane Handbook for Systematic Reviews of Interventions methodology and report results according to PRISMA guidelines. We included randomized controlled trials, non-randomized comparative studies and case series investigating adults and children with severe, life-threatening external bleeding who were treated with therapies potentially suitable for first aid providers. We assessed the certainty of the evidence and risk of bias. Outcomes were prioritized by first aid specialists based on importance for patients and decision-makers and included mortality due to bleeding, all-cause mortality, cessation of bleeding, time to cessation of bleeding, a decrease in bleeding and complications/adverse effects. Results were reported in Evidence Profiles. Results: Of the 1,051 full-text articles screened, 107 were included for analysis including 22,798 patients. The primary methods of bleeding control were tourniquets (n=49), hemostatic dressings (n=34), hemostatic devices (n= 14), pressure dressings/bandages/devices (n=8), pressure points (n=4), including two studies that reported multiple hemorrhage control methods. Overall, certainty of evidence was very low and often relied on indirect evidence and poorly controlled studies. Tourniquets were associated with a A c c e p t e d M a n u s c r i p t 2 decrease in mortality when compared with direct manual pressure. Hemostatic dressings resulted in a shorter time to hemostasis than direct manual pressure using standard dressings. Direct manual compression resulted in a shorter time to hemostasis than pressure dressings/devices. Conclusion: Overall, data regarding the control of life-threatening bleeding is of very low certainty, making it difficult to draw robust conclusions for treatment by immediate responders. While more robust data is needed on first aid treatments of life-threatening bleeding, this systematic review aggregates the most comprehensive to date to help guide recommendations.

The aim of this study was to determine if dental students would benefit from changing their initial responses to what they have deemed to be more suitable answers during high-stakes multiple-choice examinations. Students are often advised to stay with their first answers despite evidence from other fields suggesting this is not the best course for obtaining optimal final exam scores. Data were collected for 160 first-year DMD students in fall 2013 for three operative dentistry and four biochemistry exams at Tufts University School of Dental Medicine. As students take all of their exams through ExamSoft, a test-taking software application that tracks and records all changes students make during the exam period, the subjective nature of previous studies on answer changing was eliminated. The results showed that all students changed their answers on a minimum of nine questions over the seven exams, with an average of 26.55 (SD=8.8) questions changed per student. Answers changed from an incorrect to a correct response comprised nearly 65% of total answer changes, while changes from a correct to an incorrect answer encompassed slightly above 10% of answer changes. Nearly all students (99.4%) benefitted from answer-changing with a net gain of at least two correct questions, with only one student not increasing the final score. Overall, the students greatly benefitted from changing their answer choice, suggesting that dental students could be advised to change their answers from their first choice if they identify a better option when taking multiple-choice exams.