['Coeliac disease is frequently diagnosed after a long delay resulting in increased morbidity and mortality.', 'To define the parameters which have the highest impact on the cost-effectiveness of mass screening for coeliac disease.', 'A Markov model examined a coeliac disease screening programme of the healthy young-adult general population compared with a no-screening strategy. The main outcome measures were quality adjusted life-years (QALYs) and incremental cost-effectiveness ratio (ICER). Effects of variables were examined using sensitivity analyses.', 'The screening strategy resulted in a gain of 0.0027 QALYs. The ICER of screening vs. no-screening strategy was US$48,960/QALYs. The variables with the largest impact on cost effectiveness were: the time delay from symptom onset to diagnosis, the utility of adherence to a gluten-free diet (GFD) and the prevalence of coeliac disease. Screening would be cost-effective if the time delay to diagnosis is longer than 6 years and utility of GFD adherence is greater than 0.978.'] Is cost effectiveness of mass screening for coeliac disease determined by time-delay to diagnosis and quality of life on a gluten-free diet?