Analytical approach:
A decision tree was constructed to compare the two screening methods over a lifetime horizon. Life expectancy was estimated for each disease and treatment state. The perspective adopted was not explicitly reported by the authors.
Effectiveness data:
The effectiveness data were derived from published literature and from official national sources. The sources searched, the process used to identify the data, and any inclusion criteria for the estimates were not reported. The main clinical parameters included disease prevalence, the sensitivity and specificity of fine needle aspiration and calcitonin screening, the screening interval, and complication rates of thyroidectomy.
Monetary benefit and utility valuations:
Not relevant.
Measure of benefit:
The measure of benefit was life-years saved (LYS). Survival was estimated using Kaplan-Meier survival curves.
Cost data:
The cost categories included ATA guideline screening implementation costs, calcitonin screening, the cost for treating each stage of MTC, and complications due to thyroidectomy. The cost estimates were obtained from official national sources (Medicare Reimbursement Schedule) and were reported for the price year 2007. All costs were expressed in US dollars ($) and were discounted at an annual rate of 3%.
Analysis of uncertainty:
Uncertainty was assessed using one-way sensitivity analyses for various model parameters such as the prevalence of MTC, the sensitivity and specificity of the tests, calcitonin costs, the screening interval, years of surveillance, 10-year survival rate, the discount rate, patients’ age, gender and nodule size.