ERBB2 and neoplasm: For instance, among White women, we observed a reduced hazard (HR = 0.65, CI: 0.46–0.91) of dying if one has two or more friends/relatives compared to those with one or less, after controlling for age at diagnosis, time from cohort enrollment to diagnosis, income, education, marital status, insurance, addition of HER2, tumor ER status, and tumor PR status; among Black women, this association was weaker and not statistically significant (HR = 0.88, CI: 0.71–1.09).