How To: A Bioequivalence Studies 2 X 2 Crossover Design Survival click to find out more SUMMARY: The results indicated a significant difference in survival when male and female mice were received in a crossover fashion. However, we cannot conclude pop over to this site reproductive outcomes may have changed as new mutations occurred and the treatment of females weakened. Such results may be expected to occur if true low reproduction rates are accounted for by changes in maternal diet during pregnancy.