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but they vary in value for different steps. In a yin-yang balance, Author Contributions
a tradeoff between thinking and speed occurred in this study, JFK, JKA, and MAD conceived and designed the study; JFK
and user 3, a cadet, balanced it best. This surprising finding resourced, managed, and oversaw the study; JFK, NJN, and
of user judgment reinforces a principle: Caregiving engines are ART collected data; and JFK, JKA, NJN, and ART analyzed
human, and caregiving analyses have to account for that fact. data; all participated in writing. All authors approved the final
version of the manuscript.
Preference as an aspect of performance is a tricky, evolving
science, 18,19 and there is little awareness of its subtleties in the References
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Funding paring Generation 6 versus prototype Generation 7 Combat Ap-
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This project was funded by the US Army Medical Research plication Tourniquet in a manikin hemorrhage model. J Spec
and Materiel Command. Oper Med. 2016;16(1):14–17.
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The opinions or assertions contained herein are the private 17. Goolsby C, Jacobs L, Hunt RC, et al. Education program content
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or reflecting the views of the Department of Defense or US 84(1):205–210.
Government. The authors are employees of the US Govern- 18. Tversky A, Kahneman D. The framing of decisions and the psy-
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Disclosure skill to control groin-wound bleeding: use of junctional tourni-
The authors have indicated they have no financial relation- quet models on a manikin. J Spec Oper Med. 2017;17(2):39–48.
ships relevant to this article to disclose.
Tourniquet Models Compared | 41

