Fig. 4

Changes in the prevalence of unrepaired CHD and CHD subtypes in school age children during 1970–2014. a The prevalence of unrepaired CHD overall during the studied period. Thick dark blue line is the average value of prevalence, while the thin lines are 95% CIs. b The prevalence of unrepaired Septal defects (VSD and ASD), PDA and severe CHDs of the entire period. Prevalence of Septal defects, PDA and severe CHDs were represented in red, orange and light blue lines with dots, respectively. The time bins are defined by investigation time reported by studies