A meta-analysis of 61 sperm count studies revisited

Stan Becker; Kiros Berhane

doi:10.1016/S0015-0282(97)81446-X

A meta-analysis of 61 sperm count studies revisited

Stan Becker, Kiros Berhane

Bloomberg School of Public Health

Research output: Contribution to journal › Article › peer-review

Abstract

Objective: To re-examine data on sperm counts over time from 61 studies from around the world. Design: Parametric analyses and flexible nonlinear models of the relation between sperm counts and time. Main Outcome Measure(s): Mean sperm concentrations per milliliter and regression coefficients for possible trends of concentrations over time. Result(s): A significant decline was found only in U.S. studies. Conclusion(s): Studies from specific sites have found declines in sperm counts, but a world-wide decline has not been demonstrated. Rigorous assessment of statistical models should be done before conclusions are drawn. Flexible smoothing models are a useful addition to currently available analytic methods.

Original language	English (US)
Pages (from-to)	1103-1108
Number of pages	6
Journal	Fertility and sterility
Volume	67
Issue number	6
DOIs	https://doi.org/10.1016/S0015-0282(97)81446-X
State	Published - Jun 1997

Keywords

Mean sperm counts
Meta-analysis
Statistical modeling

ASJC Scopus subject areas

Reproductive Medicine
Obstetrics and Gynecology

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10.1016/S0015-0282(97)81446-X

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A meta-analysis of 61 sperm count studies revisited

Abstract

Keywords

ASJC Scopus subject areas

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