15 years ago the UK government commissioned an independent review of the primary curriculum. As a result Synthetic Phonics was made mandatory in all English and Welsh primary schools as of 2007.
"Synthetic Phonics offers the vast majority of young children the best and most direct route to becoming skilled readers and writers."Independent Review of Primary Curriculum, 2006
Around the same time the USA researched every major method to teach children how to read and concluded:
"Systematic phonics instruction produces significant benefits for students in kindergarten through 6th grade and for children having difficulty learning to read."The National Reading Panel, 2006