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The du Bois sign

James H Voelpel1, Thomas Muehlberger

  • 1Department of Plastic and Hand Surgery/Burn Center, BG Clinic Bergmannstrost, Merseburger Strasse 165, Halle/Saale, Germany. jhvoelpel@aol.com

Annals of Plastic Surgery
|January 26, 2011
PubMed

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Sign Convention

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Sign Test for Matched Pairs

The sign test for matched pairs offers a robust method for comparing two paired samples, often for the effects of an intervention in one of them. This method is very useful in situations where the underlying distribution of the data is unknown. The test compares two related samples—often pre- and post-treatment measurements on the same subjects—to determine if there are significant differences in their median values.
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Sign Test for Median of Single Population

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Sign Test for Nominal Data

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