The aetiological importance of stressful life events and psychological characteristics was assessed amongst 280 appendicectomy patients of whom 80% were classified with 'acutely inflamed' (organic) appendicitis and 20% with 'non-inflamed' (non-organic) appendicitis. Patients were compared with a community comparison group. Specific characteristics of life stressors, namely severe goal frustration for organic patients and severe threat for non-organic patients, were the best predictors of patient outcome. Whilst psychological characteristics were not useful in discriminating between patients, depression in particular, was clearly associated with both conditions, with 38% of non-organic and 28% of organic patients with depression scores in the clinical range. As the patient's clinical depression status failed to modify the effect of the life stress predictors, it was concluded that life stress played an important role in the development of the patients GI symptoms, irrespective of their clinical depression status.