High-risk esophageal varices in patients treated with locoregional therapy for hepatocellular carcinoma: Assessment with liver computed tomography

Computed tomography for the diagnosis of varices in liver cirrhosis: a systematic review and meta-analysis of observational studies

OBJECTIVES

This systematic review and meta-analysis aimed to evaluate the diagnostic accuracy of contrast-enhanced computed tomography (CT) for varices in liver cirrhosis.

METHODS

PubMed and EMBASE databases were searched for the literature identification. The area under the summary receiver operating characteristic curve (AUSROC), sensitivity, specificity, positive and negative likelihood ratio (PLR and NLR), and diagnostic odds ratio (DOR) were calculated. We performed the subgroup analyses according to the location of varices, CT technique, and study design. The study quality was assessed according to the QUADAS-2 tool.

RESULTS

Seventeen papers were eligible. The study quality was modest. The AUSROC was 0.8975 and 0.9494 for predicting any size and high-risk varices, respectively. Summary sensitivity, specificity, PLR, NLR, and DOR of CT for predicting any size and high-risk varices were 0.87/0.80/3.67/0.18/22.70 and 0.87/0.88/7.52/0.12/65.55, respectively. According to the location of varices, the AUSROC was 0.9127 for predicting any size gastric varices alone; and the AUSROC was 0.8958 and 0.9461 for predicting any size and high-risk esophageal varices alone, respectively. According to the CT technique, the AUSROC of multi-detector CT (MDCT) was 0.9047 and 0.9490 for predicting any size and high-risk varices, respectively; and the AUSROC of MDCT esophagograms for predicting any size and high-risk varices was 0.8735 and 0.9664, respectively. In the subgroup analysis of prospective studies, the AUSROC was 0.9122 and 0.9507 for predicting any size and high-risk varices, respectively.

CONCLUSION

CT had a high accuracy for the diagnosis of varices in liver cirrhosis.

Multi-reader multi-case studies using the area under the receiver operator characteristic curve as a measure of diagnostic accuracy: systematic review with a focus on quality of data reporting

INTRODUCTION

We examined the design, analysis and reporting in multi-reader multi-case (MRMC) research studies using the area under the receiver-operating curve (ROC AUC) as a measure of diagnostic performance.

METHODS

We performed a systematic literature review from 2005 to 2013 inclusive to identify a minimum 50 studies. Articles of diagnostic test accuracy in humans were identified via their citation of key methodological articles dealing with MRMC ROC AUC. Two researchers in consensus then extracted information from primary articles relating to study characteristics and design, methods for reporting study outcomes, model fitting, model assumptions, presentation of results, and interpretation of findings. Results were summarized and presented with a descriptive analysis.

RESULTS

Sixty-four full papers were retrieved from 475 identified citations and ultimately 49 articles describing 51 studies were reviewed and extracted. Radiological imaging was the index test in all. Most studies focused on lesion detection vs. characterization and used less than 10 readers. Only 6 (12%) studies trained readers in advance to use the confidence scale used to build the ROC curve. Overall, description of confidence scores, the ROC curve and its analysis was often incomplete. For example, 21 (41%) studies presented no ROC curve and only 3 (6%) described the distribution of confidence scores. Of 30 studies presenting curves, only 4 (13%) presented the data points underlying the curve, thereby allowing assessment of extrapolation. The mean change in AUC was 0.05 (-0.05 to 0.28). Non-significant change in AUC was attributed to underpowering rather than the diagnostic test failing to improve diagnostic accuracy.

CONCLUSIONS

Data reporting in MRMC studies using ROC AUC as an outcome measure is frequently incomplete, hampering understanding of methods and the reliability of results and study conclusions. Authors using this analysis should be encouraged to provide a full description of their methods and results.