Economic model
A Markov simulation model with three mutually exclusive nonabsorbent
states was used to compare the estimated cost and outcomes associated
with asthma management using standard care (SC) or SC with FeNO
monitoring to guide asthma management in Children (FeNO-SC)
(Figure 1 ). This model and according to the natural history,
have three health states were defined: “no symptoms”, “suboptimal,
control, no exacerbation”, and “asthma exacerbation” with a cycle
length of 1 week. All patients entering the model are children with no
symptoms, diagnosed with mild to moderate allergic asthma, and receiving
inhaled corticosteroids as maintenance therapy. The effectiveness
outcome was the quality-adjusted life years (QALYs). The analysis was
carried out from a societal perspective (included direct and indirect
costs). The analytic horizon was 12 months. Given the short time
horizon, no type of discount to costs or results was applied. The study
protocol was reviewed and approved by the Institutional Review Board of
University of Antioquia (No 18/2015).