title: A cost-effectiveness analysis evaluating endoscopic surveillance for gastric cancer for populations with low to intermediate risk.
abstract: BACKGROUND
  Gastric cancer (GC) surveillance based on oesophagogastroduodenoscopy (OGD) appears to be a promising strategy for GC prevention. By evaluating the cost-effectiveness of endoscopic surveillance in Singaporean Chinese, this study aimed to inform the implementation of such a program in a population with a low to intermediate GC risk.
  
  
  METHODS
  USING A REFERENCE STRATEGY OF NO OGD INTERVENTION, WE EVALUATED FOUR STRATEGIES: 2-yearly OGD surveillance, annual OGD surveillance, 2-yearly OGD screening and 2-yearly screening plus annual surveillance in Singaporean Chinese aged 50-69 years. From a perspective of the healthcare system, Markov models were built to simulate the life experience of the target population. The models projected discounted lifetime costs ($), quality adjusted life year (QALY), and incremental cost-effectiveness ratio (ICER) indicating the cost-effectiveness of each strategy against a Singapore willingness-to-pay of $46,200/QALY. Deterministic and probabilistic sensitivity analyses were used to identify the influential variables and their associated thresholds, and to quantify the influence of parameter uncertainties respectively.
  
  
  RESULTS
  With an ICER of $44,098/QALY, the annual OGD surveillance was the optimal strategy while the 2-yearly surveillance was the most cost-effective strategy (ICER = $25,949/QALY). The screening-based strategies were either extendedly dominated or cost-ineffective. The cost-effectiveness heterogeneity of the four strategies was observed across age-gender subgroups. Eight influential parameters were identified each with their specific thresholds to define the choice of optimal strategy. Accounting for the model uncertainties, the probability that the annual surveillance is the optimal strategy in Singapore was 44.5%.
  
  
  CONCLUSIONS
  Endoscopic surveillance is potentially cost-effective in the prevention of GC for populations at low to intermediate risk. Regarding program implementation, a detailed analysis of influential factors and their associated thresholds is necessary. Multiple strategies should be considered in order to recommend the right strategy for the right population.
authors.affiliation: School of Public Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors.forename: Hui Jun
authors.initials: HJ
authors.lastname: Zhou
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors.forename: Yock Young
authors.initials: YY
authors.lastname: Dan
authors.affiliation: School of Public Health, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors.forename: Nasheen
authors.initials: N
authors.lastname: Naidoo
authors.affiliation: Discipline of Pharmacy & Experimental Pharmacology, School of Biomedical Sciences & Pharmacy, University of Newcastle, Callaghan, Australia.
authors.forename: Shu Chuen
authors.initials: SC
authors.lastname: Li
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors.forename: Khay Guan
authors.initials: KG
authors.lastname: Yeoh
mesh_terms: D017677:Age Distribution; D000368:Aged; D003362:Cost-Benefit Analysis; D004724:Endoscopy / Q000191:economics*; D062665:Epidemiological Monitoring; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011336:Probability; D012306:Risk; D017678:Sex Distribution; D013274:Stomach Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control