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Challenges in Patient Enrollment and Retention in Clinical Studies for Alcoholic Hepatitis: Experience of the TREAT Consortium
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Megan Comerford Spencer Lourens Suthat Liangpunsakul Naga P. Chalasani Arun J. Sanyal Vijay H. Shah Patrick S. Kamath Puneet Puri Barry P. Katz Svetlana Radaeva David W. Crabb 《Alcoholism, clinical and experimental research》2017,41(12):2000-2006
The TREAT Consortium has carried out clinical studies on alcoholic hepatitis (AH) for over 4 years. We encountered problems with participant recruitment, retention, and eligibility for specific protocols. To improve our ability to carry out such trials, we reviewed recruitment screening logs, end of study logs, and surveyed study coordinators to learn the reasons for missing patients, why patients declined enrollment, and the number of patients eligible for treatment trials. Associations of the recruited subjects’ demographics with their adherence to follow‐up appointments were examined. Three hundred eight‐seven patients (AH and heavy drinking controls) were enrolled in the observational study, and 55 AH patients were recruited into treatment trials. About half of patients identified with AH could not be recruited; no specific reason could be determined for about two‐thirds of these. Among the patients who gave a reason for not participating, the most common reasons were feeling too sick to participate, desire to concentrate on abstinence, and lack of interest in research. Approximately a quarter of the AH patients met eligibility criteria for treatment trials for moderate or severe AH and we were able to recruit half to two‐thirds of those eligible. Approximately 35% of participants in the observational study returned for both 6‐ and 12‐month follow‐up visits. We did not identify biopsychosocial or demographic correlates of retention in the study. This analysis revealed that attempts at recruitment into trials for AH miss some subjects because of structural issues surrounding their hospital admission, and encounter a high rate of patient refusal to participate. Nonetheless, more than half of the patients who met the eligibility criteria for moderate or severe AH were entered into clinical trials. Retention rates for the observational study are relatively low. These findings need to be accounted for in clinical trial design and power analysis. 相似文献
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Lung cancer is a leading cause of cancer deaths and the incidence is rising. Most patients with lung cancer present to the clinician in a fairly advanced stage and at best only 25-30% of patients can be offered curative resection. Screening tests using sputum cytology and chest radiograph have been used with limited success. Value of low dose spiral CT scan as screening tool for lung cancer is being evaluated and its limitations include high costs, need for repeated scanning and necessity to obtain histological confirmation with additional procedures. There have been significant advances in the early diagnosis of lung cancer in high risk patient groups using bronchoscopic methods such as white light bronchoscopy, autofluorescence bronchoscopy, high magnification bronchoscopy, narrow band imaging and endobronchial ultrasound. These techniques appear to be promising tools as they might allow to visualise changes of early lung cancer and also permit sampling for histological confirmation. 相似文献
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Ayush Srivastava Anurag Srivastava Ravindra M. Pandey 《The Indian journal of surgery》2017,79(5):444-445
Randomized controlled trials have become the most respected scientific tool to measure the effectiveness of a medical therapy. The design, conduct and analysis of randomized controlled trials were developed by Sir Ronald A. Fisher, a mathematician in Great Britain. Fisher propounded that the process of randomization would equally distribute all the known and even unknown covariates in the two or more comparison groups, so that any difference observed could be ascribed to treatment effect. Today, we observe that in many situations, this prediction of Fisher does not stand true; hence, adaptive randomization schedules have been designed to adjust for major imbalance in important covariates. Present essay unravels some weaknesses inherent in Fisherian concept of randomized controlled trial. 相似文献
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Soha S. Abdelmoneim Jayant Talwalkar Saurabh Sethi Patrick Kamath Mohamed Mahmoud Fahmy Fathalla Benjamin R. Kipp Michael B. Campion Amy C. Clayton Kevin C. Halling Vijay H. Shah 《Liver international》2010,30(2):191-197
Background/Aims: Peripheral circulating endothelial cells (CEC) have been proposed as a prognostic marker in cardiovascular diseases. Cirrhosis and portal hypertension are associated with vascular injury yet little is known about CEC count in these conditions. Therefore, we evaluated CEC count in patients with cirrhosis, and correlated it with markers of portal hypertension/disease severity. Patients/Methods: Fifteen patients with cirrhosis/portal hypertension and 15 matched controls were prospectively recruited for study participation. An automated rare cell analysis system was used to enumerate CEC from peripheral blood and correlated with clinical features. Results: Median CEC levels were significantly higher in patients with cirrhosis as compared with controls (median [interquartile range (IQR)]; cirrhosis: 73.7 cells/4 ml [53.7–140.3]; controls: 28.7 cells/4 ml [21–58.7]; P=0.021). Ratio of CEC to platelet count (CEC/PC) also distinguished patients with cirrhosis from controls (IQR; cirrhosis: 0.723 [0.396–1.672]; controls: 0.126 [0.103–0.333]; P<0.001). Receiver operator characteristic analysis revealed that CEC cut‐off of 42 cells/4 ml showed sensitivity of 87% and specificity of 74% for differentiating cirrhosis from controls (AUC: 0.74), while CEC/PC ratio at 0.21 showed sensitivity of 100% and specificity of 73% (AUC: 0.89). Furthermore, CEC/PC index was significantly elevated in patients with hepatic decompensation as defined by Child B/C (P<0.05). The intra‐ and interobserver variability correlation coefficients for CEC measurement were 0.9989 and 0.9986 respectively. Conclusion: Median CEC count and CEC/PC ratio are significantly elevated in patients with cirrhosis, with CEC/PC also increased in patients with decompensated cirrhosis. These data provide rationale for larger validation studies to assess if CEC may have prognostic utility in patients with cirrhosis and portal hypertension. 相似文献