MKI67 and obesity disorder: When we examined the associations between nulliparity, obesity, HT use and subtypes of HR+ tumors defined by cross‐classification of levels of KI67 and histologic grade (Table 4), we observed nulliparity to be more strongly associated with tumors expressing higher levels of KI67 and this association remained significant after accounting for grade (p‐value = 0.04) and was not modified by grade (p_interaction = 0.37).