Govert Veldhuijzen

161 The D-GESQ captures patient satisfaction as a key quality indicator of gastrointestinal endoscopy measure components of satisfaction that could help identifying specific targets for improvement for a given endoscopy department. Patients undergoing endoscopy under propofol sedation were included in the original study and in the Korean validation study of the original questionnaire (the K-GESQ), whilst this was an exclusion criterion in our study. 26 We did so because many questions could not be answered reliably after propofol sedation (for example item pain during endoscopy). Interestingly, in a study in 1104 patients in Romania (R-GESQ), that used the GESQ to compare propofol sedation versus unsedated endoscopy, this effect became visible as patients with propofol scored significantly lower procedural pain (5.2 versus 14.1%). 27 In addition, propofol sedation induces euphoria in nearly half of the patients undergoing elective endoscopy which might affect the quality of the answers. 28 Both K-GESQ and R-GESQ has been validated in populations that were younger and contained a higher proportion of females compared to our sample. Our results show that patients with prior experience in undergoing endoscopic procedures, especially exceeding more than two prior endoscopies, reported higher levels of satisfaction. Disabled patients scored lower levels of satisfaction which is also known from previous studies. 29,30 Strengths and limitations In our study, the rate of missing data was 0%. This is exceptionally low compared with a maximum missing rate of 50% for some items in the original article and 1.4% in the K-GESQ. Our study has some limitations. The development of a reliable questionnaire depends on the patient sample that participates and how the questions are interpreted by them. To eliminate bias, we utilized the think-aloud method. The challenge when translating a questionnaire is that it must be adapted in a culturally relevant and comprehensible form while maintaining the intention and meaning of the original questions. 31 By performing the translation and validation according to the WHO guidelines 13 , we ensured optimal comparability between the original GESQ from the UK 11 and this Dutch translation. To be able to also screen for early to mid-term complications after endoscopy, we e-mailed the D-GESQ 30 days after endoscopy. The survey response rate was much lower in our study then in the original study, 21.3% compared to 86.2%. In the original study, patients had to mail their completed questionnaire in a prepaid envelope. Earlier research has shown that patients were more satisfied when surveys could be completed on site compared to sending by post or email. 32 We sent an automated hyperlink by e-mail instead of a paper version by mail in the original study. We strived to lower the threshold to start and complete the questionnaire so that selection bias would be 8