During the SIGGAR trial, there were 9,218 patients aged 55 years or over, who were referred to one of 21 participating hospitals (listed above) with symptoms of bowel cancer during the study period. Of these patients, 734 were not considered as eligible for the SIGGAR study.
The SIGGAR trial included 5,448 patients who gave their consent to be randomly assigned to receive virtual colonoscopy or barium enema (trial 1) or virtual colonoscopy or colonoscopy (trial 2). Of these, 64 patients indicated that they did not want their data to be used for the purpose of the study; therefore, these patients were excluded.
In addition 3,036 were considered as eligible for the study and registered but were not randomised as a result of either doctor or patient preference. However, we require their de-identified data in order to ensure that the results of our findings are as generalisable as possible to all patients who need to be investigated because they have symptoms of bowel cancer.
The data collected as part of the SIGGAR study are also being used in a follow-up study called SOCCER.