title: An application of multivariate ranks to assess effects from combining factors: metal exposures and semen analysis outcomes.
abstract: In studies of environmental effects on human health outcomes, it is often difficult to assess the effects of a group of exposure variables when the individual exposures do not appear to have statistically significant effects. To address this situation, we propose a method of U-scores applied to subsets of multivariate data. We illustrate the usefulness of this approach by applying it to data collected as part of a study on the effects of metal exposure on human semen parameters. In this analysis, profiles (pairs) of metals containing copper and/or manganese were negatively correlated with total motile sperm and profiles containing copper were negatively correlated with sperm morphology; profiles containing selenium and chromium were positively correlated with total motile sperm.
authors.affiliation: Department of Statistics and Probability, Michigan State University, East Lansing, MI 48824, USA.
authors.forename: R V
authors.initials: RV
authors.lastname: Ramamoorthi
authors.forename: M G
authors.initials: MG
authors.lastname: Rossano
authors.forename: N
authors.initials: N
authors.lastname: Paneth
authors.forename: J C
authors.initials: JC
authors.lastname: Gardiner
authors.forename: M P
authors.initials: MP
authors.lastname: Diamond
authors.forename: E
authors.initials: E
authors.lastname: Puscheck
authors.forename: D C
authors.initials: DC
authors.lastname: Daly
authors.forename: R C
authors.initials: RC
authors.lastname: Potter
authors.forename: J J
authors.initials: JJ
authors.lastname: Wirth
mesh_terms: D004781:Environmental Exposure / Q000706:statistics & numerical data*; D004782:Environmental Health; D006801:Humans; D008297:Male; D008670:Metals / Q000494:pharmacology*; D015233:Models, Statistical; D012661:Semen / Q000187:drug effects / Q000502:physiology*
chemical_list: D008670:Metals