Narcotic usage was collected for first 48 hours post-operatively after breast reconstruction. The type and amount of each narcotic administered were each converted to the morphine equivalent amount that would be orally administered to achieve the same event. This term is known as the oral morphine equivalent (OME). Narcotic usage was assessed between the group receiving transversus abdominis plane (TAP) nerve block compared to the group receiving the placebo control. The outcome is reported as the observed OME for each group.

Post-operative Pain Score is defined using Visual Analog Scale (VAS), a patient-reported pain score based on viewing a graphic of a scale 0 to 10, and indicating pain level. Each participant was asked about 48 hours after breast reconstruction to indicate their their perceived pain according on the VAS scale. Higher scores represent greater pain. The outcome is reported as the mean VAS score at 48 hours, with standard deviation.

Odansetron by intravenous administration was used to control nausea (ie, an anti-emetic drug). Anti-emetic usage was collected for first 48 hours post-operatively after breast reconstruction for the group receiving transversus abdominis plane (TAP) nerve block compared to the group receiving the placebo control. The outcome is reported as the mean quantity of Odansetron in milligrams (mg) administered to each group, with standard deviation.

Time to ambulation is defined as the amount of time, from midnight on post-operative Day 1 (ie, first midnight following the surgery), to when the participant to be able to stand up and walk a few steps post-operatively. The assessment of whether or not the participant was able to walk was subjective on the part of the shift nurse (ie, no defined number of steps nor quantitative assessment of gait or stability), and was not explicitly defined in the protocol or elsewhere. The outcome is reported as the time to ambulation in days, with standard deviation, for the group receiving transversus abdominis plane (TAP) nerve block and the group receiving the placebo control.

Time to first bowel movement is defined as the amount of time, from midnight on post-operative Day 1 (ie, first midnight following the surgery), to when the participant was to be able to pass a stool post-operatively. The outcome is reported as the time in days, with standard deviation, for the group receiving transversus abdominis plane (TAP) nerve block and the group receiving the placebo control.

Quality of life for the study groups was assessed with the BREAST-Q questionnaire, a survey set of 6 pre-operative questionnaires comprised of 58 questions, and 15 post-operative questionnaires, collected 2 to 6 months after surgery, which is comprised of 109 questions. The results range for the pre-operative and post-operative questionnaire sets is 0 to 269 and 0 to 462, respectively. Because the baseline and post-operative domains are different, the BREAST-Q survey is not a measure of quality of life change over time. The Breast Q questionnaire was validated by Pusic, et al (citation provided). Higher scores for a domain represents better quality of life. The outcome is reported as the mean for each group and timepoint, with standard deviation.

Most participants were lost to follow-up, and did not return the case report form (CRF) for this patient-reported Quality of Life (QoL) data