4. Allocation of studies to different subgroups (categories).

Subgroups		Barker 1995	Blythe 2006	Chen 2014	Ford 2009	Hurford 1994	Hurry 2007	Levy 1997	Levy 1999	Lovett 1990	Lovett 2000	McArthur 2015a	McArthur 2015b	Savage 2003	Savage 2005
Training type	Phonics only	X	—	—	—	—	—	X	X	—	—	X	X	—	—
	Phonics + phoneme awareness	—	X	—	X	X	X	—	—	—	X	—	—	X	X
	Phonics + sight words	—	—	X	—	—	—	—	—	X	—	—	—	—	—
Training intensity	< 2 hours/week	X	X	X	X	X	X	X	X	—	—	—	—	X	X
	≥ 2 hours/week	—	—	—	—	—	—	—	—	X	X	X	X	—	—
Training duration	< 3 months	X	X	X	X	—	—	X	X	X	X	X	X	X	X
	≥ 3 months	—	—	—	—	X	X	—	—	—	—	—	—	—	—
Training group size	1	—	X	—	X	X	X	X	X	—	—	X	X	—	—
	≤ 5	X	—	X	—	—	—	—	—	X	X	—	—	X	X
Training administrator	Human	—	—	X	—	—	X	X	X	X	X	—	—	X	X
	Computer	X	X	—	X	X	—	—	—	—	—	X	X	—	—