We conducted a time and motion (T&M) study to quantify patient chair time and active HCP time associated with SC and IV trastuzumab within the PrefHer trial (NCT01401166), where patients with HER2‐positive early breast cancer were given four cycles of SC trastuzumab (by SID [Cohort 1] or HHS [Cohort 2]) followed by four cycles of IV or vice versa as part of 18 standard cycles 8, 9. Here, ERBB2 is linked to breast carcinoma.