Annelotte van Bommel

87 Organizational factors affect the use of immediate breast reconstruction In Figure 1 , the variation between hospitals in the use of IBR after mastectomy for DCIS in the Netherlands is demonstrated. Case-mix adjustments for patient and tumor factors significantly affecting the use of IBR were performed. Also, adjustments for hospital organizational factors were performed, due to the characteristics of a multilevel analysis. Adjusted data demonstrated a decrease in hospital variation in the use of IBR from 0–80% to 0–49%. Figure 1. Funnel plot demonstrating the variation in the use of immediate breast reconstruction for ductal carcinoma in situ between hospitals in the Netherlands with and without case-mix correc- tion for patient and tumor factors, combined withmultilevel analyses to adjust for hospital factors. In the adjusted data; Case-mix correction for age, grade and social economic state combined with mutilevel analysis to correct for hospital organizational factors. Invasive breast cancer The hospital organizational factors (hospital type, hospital volume, percentage of mastectomies, number of weeklyMDTmeetings, number of plastic surgeons per 100 newdiagnoses, number of breast surgeons per 100 newdiagnoses and the attendance of a plastic surgeon at weeklyMDTmeeting) demonstrated to significantly affect IBR rates inunivariableanalyses andwere included in themultivariablemodel ( Table 3 ). 95%Cl Observedvaluesfor districthospitals Adjustedvaluesfor districthospitals Observedvaluesfor teachinghospitals Adjustedvaluesfor teachinghospitals Observedvaluesfor universityhospitals Adjustedvaluesfor universityhospitals Observedvaluesfor cancerspecifichospitals Adjustedvaluesfor cancerspecifichospitals 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% 0 20 40 60 80 100 120 140 Percentage of patients undergoing an immediate breast reconstruction Number of patients undergoing a mastectomy (for DCIS) 5