Benchmarking is a procedure whereby an organisation compares its own performance in specific areas with the performance of peer institutions. In England the Atlas of Variation is a helpful tool, see https://fingertips.phe.org.uk/profile/atlas-of-variation this compares unwarranted variation in health care expenditure across England.Other examples would include the Cancer Registries data which is collected across Europe.http://www.euro.who.int/en/data-and-evidence/interactive-atlases

31 It is stated that nitric oxide (NO) inhibits the relaxation of the lower oesophageal sphincter (LOS) and that sildenafil is given for treating achalasia. As far as I know, sildenafil acts to increase the guanine monophosphate (GMP), just as NO uses the same mechanism to relax the LOS. Could you explain this paradox?

32 In Kumar and Clark Clinical Medicine you mention that auscultation is not important in cases of gastrointestinal disorders, but Harrison's Principles of Internal Medicine gives this as being of equal importance because succussion splash and bowel sounds can help in presumptive diagnosis. Succussion splash indicates gastric obstruction (e.g. gastroparesis) and likewise bowel sounds can help determine the status of developing ileus. Would you agree that this is therefore a diagnostic tool?

33 Is it hazardous to give aspirin in the antiplatelet doses (75-325 mg/day) to a patient with a past history of haematemesis proved to be from a peptic ulcer?

34 How can upper gastrointestinal (GI) bleeding be distinguished from lower GI bleeding by using faecal analysis?

35 In upper gastrointestinal bleeding, without knowing the cause or source of bleeding, why do we give proton pump inhibitors (PPIs, e.g. omeprazole)? What is the role of these, if the source of bleeding is not peptic or duodenal ulcer?

36 Why is the incidence of coeliac disease increasing in many countries?

37 Are small amounts of gluten harmful to a patient with coeliac disease?

38 I refer to the treatment of complications related to diverticular disease. Under 'bleeding' you mention that 'Persistent bleeding can often be arrested by undertaking an "instant" barium enema, which acts to plug the offending diverticulum'. When I mentioned this to my consultant he said he had never heard of this. Could you clarify how this would work and where I could obtain more information?

39 In children with abdominal pain and fever, does a white cell count help establish a diagnosis of appendicitis?

40 I have always been taught that ulcerative colitis only affects the large bowel with some associated proctitis. I read in your chapter on gastrointestinal disease that it can cause mouth ulcers and am now confused.