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Pattern recognition in menstrual bleeding diaries by statistical cluster analysis
Christoph Gerlinger1, Jens Wessel, Gerd Kallischnigg
1Global Clinical Statistics, Bayer Schering Pharma AG, Müllerstrasse 178, 13342 Berlin, Germany. christoph.gerlinger@bayerhealthcare.com
BMC Women'S Health
|July 18, 2009
Summary
This study introduces a statistical method to classify menstrual bleeding patterns from clinical trials. Ward
Area of Science:
- Gynecology
- Statistics
- Pharmacology
Background:
- Clinically relevant bleeding patterns require objective description.
- Existing methods lack treatment independence for bleeding pattern analysis.
Purpose of the Study:
- To identify a treatment-independent statistical method for describing bleeding patterns.
- To analyze menstrual bleeding diaries from clinical studies involving sex hormone drugs.
Main Methods:
- Applied four cluster analysis methods: single, average, complete linkage, and Ward's method.
- Determined the optimal number of clusters using statistical criteria (semi-partial R2, cubic cluster criterion, pseudo-F, pseudo-t2).
- Assessed the interpretability of results from a gynecological perspective.
Main Results:
- Ward's method effectively produced distinct clusters, unlike other methods.
- Identified six distinct bleeding patterns: two desirable and four undesirable.
- Successfully separated cyclic and non-cyclic bleeding patterns.
Conclusions:
- Ward's cluster analysis provides a robust, treatment-independent method for categorizing bleeding patterns.
- Facilitates comparison and categorization of medications and devices impacting menstrual bleeding.
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