Costs from NHS perspective were calculated by the amount that the Regional Health Authority reimbursed to health providers.
Therefore healthcare expenditures from the health insurance perspective were calculated by summing amounts reimbursed by national health insurance for all healthcare resources consumed by calendar year, overall and by type of resource.
The payer's perspective was calculated using direct costs of pretravel health consultations, chemoprophylaxis with adverse events treatment, and malaria treatment.
Costs were assessed from the health care system perspective, and were calculated according to the French Diagnosis-Related Group (DRG) system.
All costs were assessed from the societal perspective and were calculated per patient by multiplying the volume of resource use by the unit costs.
Except for the treatment costs of home phototherapy, all costs were assessed from the societal perspective and were calculated per patient by multiplying the volume of resource use by the unit costs.
Putting these results into perspective, population attributable risks were calculated (Levin, 1953; Taylor, 1977) for the main exposures, namely, reflux, high BMI, and tobacco smoking, using another Swedish database, incorporating oesophageal adenocarcinoma data (Lofdahl et al, 2008).
As the cost-effectiveness analysis is carried out from the third-party payer perspective only direct costs were calculated in this study, including those relating to the screening itself, treatment and diagnostic tests (adenoma and CRC only), complications from colonoscopy and surveillance (adenoma only).
Costs per patient year were calculated from four perspectives: those of patients, the Rotterdam Eye Hospital (REH), Dutch healthcare system, and society.
Both cost effectiveness and cost utility were calculated from the perspectives of the public payer and the payer, with an analysis horizon of 26 years.
