Interobserver variation in assessment of gastroduodenal lesions associated with non-steroidal anti-inflammatory drugs.

Video endoscopic images were used to investigate whether gastroenterologists could agree on the definition of lesions within the stomach seen at endoscopy, with particular reference to those seen in patients taking non-steroidal anti-inflammatory drugs. Seven experienced endoscopists, unaware of the patients' clinical history or drug consumption, recorded their classification for 93 randomised video images of gastric lesions. There was complete agreement in the diagnosis of ulceration for nine images from patients who were not taking non-steroidal anti-inflammatory drugs; eight of nine were classified as deep ulcers, with 86% agreement for this subclassification. By contrast, the overall agreement for lesions in patients taking non-steroidal anti-inflammatory drugs was only 55%. Only nine of 44 ulcers were subclassified as deep, and there was considerable cross classification of non-haemorrhagic erosions and ulcers. In conclusion, ulcers that occur in patients taking non-steroidal anti-inflammatory drugs differ from those in patients who are not taking these drugs in that they are often more superficial and difficult to distinguish from erosions. The prognostic importance of these lesions is, therefore, uncertain.