These estimates are a potential source of bias because the true underlying proportion of former drinkers may be higher or lower.
In fact, recent studies have shown that much of the variability identified in peripheral blood DNA methylation profiles represents variation in the underlying proportion of blood cell types [ 38, 39].
Because of inability to determine microbiologic etiology of many SSTIs, and potential bias with respect to which SSTIs get cultured, it is difficult to infer the true underlying proportion of SSTIs due to given pathogens.
To examine if the differences in methylation between donor and recipients represent differences in the underlying proportion of blood cell types within the sample, we ranked the loci on the arrays based on their prior association with blood leukocyte methylation [ 38, 39] which has defined blood cell specific differentially methylated regions.
This can be achieved by using the Dirichlet-multinomial (DM) model (Mosimann, 1962), which assumes the underlying proportions of the multinomial model come from a Dirichlet distribution.
Like a fine old house, Mozart's "Così fan Tutte" is an opera that relies on an underlying sense of proportion; inflating it to fit in a 3,000-seat 3,000-seate results in soperaing akin to a McMansion.
Hepatitis C has been shown to be endemic in Irish prisons [ 9] and substance misuse is an underlying problem for a large proportion of prisoners [ 10].
One fourth of those hospitalized with pandemic (H1N1) 2009 influenza in Kenya had an underlying medical condition, a lower proportion than in the United States (73%), Ireland (50%), and Chile (37%) (5, 9, 10 ).
In part, clustering of breast cancer in a family is a result of chance, because breast cancer is so frequent; in some families, the clustering is the result of shared environmental risk factors; and in a proportion of families an underlying genetic defect will be the culprit.
The proportion of controls with an underlying disease, as well as those who were immunosuppressed, was lower compared with patients not tested for resistance (Table 3).
