Three clinical studies have evaluated the change in the QOL of patients with malignant biliary obstruction after of endoscopic stenting. Ballinger et al evaluated 19 patients with unresectable pancreatic carcinoma before stenting and upto 12 weeks or death after stenting. The Rotterdam Symptom Checklist and the Hospital Anxiety and Depression Scale were used. Significant improvements were seen in the parameters of mood, indigestion, appetite and level of activity. Luman et al studied 47 inoperable patients with malignant biliary strictures. The European Organisation for Research and Treatment of Cancer QOL questionnaire (EORTC QLQ-C30) was used at baseline and 1 month after stenting. For patients successfully completing the follow up, significant improvement in emotional, cognitive , and global health scores was found after stenting. In addition to the expected improvement in pruritis and jaundice , anorexia, diarrhea and sleep pattern were also improved. Abraham et al studied 50 patients with malignant biliary obstruction without liver metastasis considered non surgical candidates, and undergoing palliative biliary stenting. The SF-36 Health Survey Questionnaire was used to quantify QOL at baseline and 1 month after stent insertion. Follow up data was available for only 26 patients. Among these patients a significant reduction in the bilirubin level was associated with improvement in the social function and mental health. A high baseline bilirubin (> 14mg/dL) was associated with a lack of improvement at 1 month follow up.