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Background: Hepatocellular carcinoma (HCC) is the fastest increasing cause of cancer death in Australia. A recent Australian consensus guidelines recommended HCC surveillance for cirrhotic patients and non-cirrhotic chronic hepatitis B (CHB) patients at gender and age specific cut-offs. A cost-effectiveness model was then developed to assess surveillance strategies in Australia. Methods: A microsimulation model was used to evaluate three strategies: biannual ultrasound, biannual ultrasound with alpha-fetoprotein (AFP) and no formal surveillance for patients having one of the conditions: non-cirrhotic CHB, compensated cirrhosis or decompensated cirrhosis. One-way and probabilistic sensitivity analyses as well as scenario and threshold analyses were conducted to account for uncertainties: including exclusive surveillance of CHB, compensated cirrhosis or decompensated cirrhosis populations; impact of obesity on ultrasound sensitivity; real-world adherence rate; and different cohort's ranges of ages. Results: Sixty HCC surveillance scenarios were considered for the baseline population. The ultrasound + AFP strategy was the most cost-effective with incremental cost-effectiveness ratios (ICER) compared to no surveillance falling below the willingness-to-pay threshold of A$50,000 per quality-adjusted life year (QALY) at all age ranges. Ultrasound alone was also cost-effective, but the strategy was dominated by ultrasound + AFP. Surveillance was cost-effective in the compensated and decompensated cirrhosis populations alone (ICERs < $30,000), but not cost-effective in the CHB population (ICERs > $100,000). Obesity could decrease the diagnostic performance of ultrasound, which in turn, reduce the cost-effectiveness of ultrasound ± AFP, but the strategies remained cost-effective. Conclusions: HCC surveillance based on Australian recommendations using biannual ultrasound ± AFP was cost-effective. [ABSTRACT FROM AUTHOR]

Concrete-filled double-skin steel tubular (CFDST) columns composed of outer stainless-steel skin have grown increasingly popular in structural applications on account of their attractive appearance, ductility, resistance to corrosion, fire resistance and easy maintenance. However, only one numerical study of the behavior of rectangular CFDST short columns with outer stainless steel tube has been reported. This paper presents the numerical analysis and design of axially loaded rectangular CFDST short columns where the outer tube is made of stainless-steel. A finite element model is created for analyzing the responses of rectangular CFDST short columns. The numerical analysis accounts for the confinement mechanism of concrete, strain hardening of stainless steel and imperfection of steel tubes. A comparative study of numerically predicted and experimentally observed behavior is presented to gain an appreciation for the accuracy of the developed numerical model. A parametric study is undertaken, investigating the performance of a series of rectangular CFDST columns by varying the concrete strength, load distribution, cross-section shape and tube thickness. The ultimate axial strengths predicted using Australia/New Zealand Standard for composite structures are compared against experimental results. It is demonstrated that the numerical model predicts well the responses of CFDST columns where the outer skin is made of stainless steel. Australia/New Zealand Standard yields the accurate predictions of the ultimate axial strengths of rectangular CFDST columns with outer stainless-steel tube. • Finite element model for simulating rectangular CFDST short columns is presented. • The model consider confinement, stainless-steel strain hardening and imperfections. • Studies on the behavior of CFDST columns with outer stainless-steel skin are given. • The model developed simulates well the responses of CFDST short columns. [ABSTRACT FROM AUTHOR]