| | | | | | The Medical Algorithms Project |
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| Chapter : | ch39. Decisional Analysis | Section : | Performance Measures | | Algorithm of Grimes and Schulz for Distinguishing Rates, Proportions and Ratios | | Copyright (c) 2008-2010, Institute for Algorithmic Medicine, Houston, TX, USA. All rights reserved. |
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Overview :
Grimes and Schulz developed a simple algorithm for
distinguishing between a rate, ratio and proportion. The authors are from
Family Health International in Research Triangle Park (Raleigh-Durham), North
Carolina.
Questions:
(1) Is the numerator included in the denominator?
(2) Is time included in the denominator?
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Numerator in Denominator
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Time in Denominator
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Calculation
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no
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NA
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ratio
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yes
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no
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proportion
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yes
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yes
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rate
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| | References: | |
Grimes DA,
Schulz KF. An overview of clinical research: The lay of the land. Lancet. 2002;
359: 57-61 (Figure 3, page 60).
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