A careful review of the existing literature assessing the association
between RPA and EOC risk yielded the discovery of several important
limitations regarding the manner in which RPA was measured and
modeled, which could explain why many of the cohort studies resulted
in null findings. Additionally, many individual studies of EOC are
plagued by low EOC case numbers, which may preclude the ability to
observe statistically significant associations among various subgroups
of women. The reasons for the positive associations observed in cohort
studies remain unclear and have been a consistent source of debate in
the literature.While competing biological theories described above provide
potential plausibility for increased risk of illness among women
who are excessive exercisers, it is more likely that the positive associations
observed in the EOC are due to non-causal factors