Though the model we built in the study could not completely reflect the current guidelines of gBRCA screening, especially for those lower than 50 years old who are already recommended to receive gBRCA testing now, the results from our model indeed provide evidence that incorporating PARPi secondary to gBRCA testing for TNBC and HER2-negative BC patients are cost-effective against the WTP in both China and the USA. Here, ERBB2 is linked to breast cancer.