Figure 1.

Markov Model to assess the cost-effectiveness of MS/MS-based neonatal screening for GA-I. Following the initial screening decision, GA-I can be diagnosed either based on the screening result, based on the clinical sign of macrocephaly (early diagnosis) or following an acute encephalopathic crisis (diagnosis on clinical sign). Regarding the health state, individuals with GA-I can either be healthy or have only mild symptoms (asymptomatic diagnosed), suffer from severe movement disorder (impaired), or have died (death). Healthy individuals with GA-I in whom the diagnosis has not been established (undiagnosed) have a higher risk to experience acute encephalopathic crisis than healthy children with known diagnosis (asymptomatic diagnosed).