An application of multivariate ranks to assess effects from combining factors: Metal exposures and semen analysis outcomes.

Ramamoorthi, R. V.; Rossano, M. G.; Paneth, N.; Gardiner, J. C.; Diamond, M. P.; Puscheck, E.; Daly, D. C.; Potter, R. C.; Wirth, J. J.

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. Copyright © 2008 John Wiley & Sons, Ltd.

Statistics in Medicine, 2008, Vol 27, Issue 18, p3503

0277-6715

Academic Journal

10.1002/sim.3236