Response rate and respondent characteristics
In 2014, the response for the TCI and of the evaluation questionnaire was 17.6% (121/687) and 17.7% (123/695), respectively. In 2016, the response for both questionnaires was 28.6% (107/374), and in 2019 it was 25.0% (150/600). Approximately 50% of the respondents in 2014, 2016 and 2019 were surgeons (including residents and fellows) (Appendix 5). Of the interviewees, the years of experience in the current function were 2–32 years. Fifty-four percent of the interviewees were male. Detailed characteristics of the interviewees are presented in Appendix 6.