Table 5 Effect Sizes by Research Design, Level of Support, and Dependent Variable (N= 23, k =111)

	Category	number of studies (N)	k2)	Mean PND	Mean IRD	Mean Tau-U
Research design	Multiple-baseline design	18	85	.964	.973	.982
	Reversal design	3	13	.810	.850	.880
	Baseline–intervention–maintenance design	3	13	.945	.945	.918
Level of support	Individual-level support	17	78	.933	.951	.963
	Class-wide + individual-level support	4	24	.965	.962	.954
	Class-wide support	1	3	.938	.938	.964
	Grade-level support	1	6	1.000	1.000	1.000
Dependent variable	Problem behavior	21	64	.947	.962	.974
	Desirable behavior	13	41	.936	.944	.943
	Social interaction	2	6	.962	.962	.978

N : number of studies. (In the study by Song et al. (2018), both a multiple-baseline-across-settings design and an A-B design were reported and therefore coded separately. Thus, the sum of the number of studies by research design may not equal the total number of studies)
k : number of AB comparison units
(a single study could include multiple disability types, the sum of the number of studies by disability type may not equal the total number of studies)