Selection Bias in Occupational Sperm Studies
نویسندگان
چکیده
منابع مشابه
Selection bias in occupational sperm studies.
Participation rates in sperm studies are typically 25-50%, and therefore it is a matter of concern whether the men who provide semen samples truly reflect the parent population. The authors analyzed data from three Danish occupational sperm studies and evaluated the relation between age and occurrence of subfertility to participation and provision of semen samples. Age and subfertility were fou...
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The advent of multiple regression analyses of natural selection has facilitated estimates of both the direct and indirect effects of selection on many traits in numerous organisms. However, low power in selection studies has possibly led to a bias in our assessment of the levels of selection shaping natural populations. Using calculations and simulations based on the statistical properties of s...
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ژورنال
عنوان ژورنال: American Journal of Epidemiology
سال: 1998
ISSN: 0002-9262,1476-6256
DOI: 10.1093/oxfordjournals.aje.a009509