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When power calculations won’t do: Fermi approximation of animal numbers

All animal protocols need quantitative justification of animal numbers, but not all will need power calculations.

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Fig. 1: Animal numbers decision tree.

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Acknowledgements

The author thanks C. Garvan and T. Vasilopoulos (Statistics in Anesthesiology Research (STAR) Core, University of Florida, USA) for their helpful comments on an earlier version of this manuscript.

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Correspondence to Penny S. Reynolds.

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The author declares no competing interests. The author discloses membership with the University of Florida IACUC committee.

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Reynolds, P.S. When power calculations won’t do: Fermi approximation of animal numbers. Lab Anim 48, 249–253 (2019). https://doi.org/10.1038/s41684-019-0370-2

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