Annelotte van Bommel

148 MATERIALS AND METHODS Study population Twenty-nine hospitals (1/3 rd of the total number of hospitals in the Netherlands), serving varying patient volumes and proportions of patients undergoing IBR, were selected from theNetherlands Cancer Registry (NCR) to participate in the survey. 16,17 The selection of patients eligible for the present study consisted of female breast cancer patients from the age of 18 years and surgically treated for primary breast cancer or DCIS by mastectomy either with or without IBR between January 2013 and October 2014. Patients with distant metastases were excluded. From January 8 th 2015, the identified patients were invited to participate in an anonymous, self- administered survey and consented to the use of the data for the purpose of this study. Responses were collected until July 30 th 2015. Approval from the Committee of Privacy of the NCR was obtained for this study. The Medical Ethical Committee of the University Medical Center Groningen (METc2014/473) declared the Medical Research (Human Subjects) Act was not applicable for this study. Questionnaire Health-related quality of life was assessed using the BREAST-Q. This validated PROM is available in Dutch. Patients without IBR completed the postoperative BREAST-Q mastectomy module and patients who had received IBR completed the postoperative BREAST-Q reconstruction module. 18 Both modules have multiple domains examining health related health-related quality of life (perceived psychosocial, physical and sexual well-being) and patient satisfaction with the treatment result (satisfaction with breasts) in common. Every domain of the BREAST-Q has 4 to 16 items and the raw domain scores expressing the extent of satisfaction or well-being are transformed to Q-scores ranging from 0 (low) to 100 (high). 19 In addition, patient characteristics (age, educational level, marital/ relationship status, working status, nationality, length and weight, comorbidities, breast size andmenopausal state) were asked. Information on breast reconstruction (no reconstruction, immediate reconstruction, delayed reconstruction), type of reconstruction, nipple reconstruction and additional procedures to achieve a favorable result were included as treatment characteristics.