When there is the limitation of a small number of comparisons for some potential modifiers in carrying out subgroup analyses on these variables, we will perform the sensitivity analyses by omitting specific trials from the overall analysis.
As a test of robustness, we estimated associations according to race/ethnicity by modeling product interaction terms for the exposure and potential modifier, in addition to lower-order terms and covariates, in whole-sample regression models controlling for all covariates.
Whilst it is clearly interesting to know the effect of BRCA1/2 alone, women undergoing testing will want to know what their own specific risk of breast and ovarian cancer are, including that contributed by other potential "modifier" genes in their family.
We investigated the relation between lifetime alcohol intake and breast cancer risk in Japanese Americans by various potential modifiers, including smoking (never versus ever), intake of soy and folate, BMI, and use of menopausal hormones (among postmenopausal women) (Table 4).
Modifiers were evaluated on the multiplicative scale by inspecting PRs stratified by the potential modifier and by performing likelihood ratio tests.
For the community-level effect modification, random-effect meta-regression models were used by including potential effect modifiers in the random-effect meta-analysis to examine their contribution to the observed variation in the effect estimates among the communities.
That mutations in ADAMTSL2 cause different phenotypes in humans, dogs and mice suggests potential modifier genes in the respective species.
Several sensitivity analyses were performed, stratifying the analysis by potential effect modifiers (SGA, preterm, change in type of cooking) and the results remained stable (see Additional file 4).
The manuscript by Parry and Brooks addresses polymorphisms in HLA-DQ and HLA-DR as potential modifiers of susceptibility and resistance in Type 1 Diabetes (T1D).
Other potential modifiers of lung disease in ATD include NOS3, GSTP1, TNF and IL10.
