Table 5.

Effect Sizes by Tutoring Condition and Difficulty Status

	Contrast tutoring condition
	WPs vs.
Variable	Control	NCs	NCs vs. Control	Contrast difficulty status: MD vs. MDRD
Number combinations	+0.62 (0.19 to 1.04)	+0.01 (−0.41 to 0.43)	+0.55 (0.14 to 0.97)	+0.43 (0.08 to 0.77)
Procedural calculations	+0.53 (0.11 to 0.96)	+0.31 (−0.12 to 0.73)	+0.27 (−0.15 to 0.68)	+0.31 (−0.03 to 0.65)
Word problems
Find X	+0.36 (−0.06 to 0.78)	+0.26 (−0.17 to 0.68)	+0.11 (−0.30 to 0.52)	+0.69 (0.34 to 1.04)
Number Sentences	+0.74 (0.31 to 1.18)	+0.73 (0.30 to 1.17)	+0.01 (−0.40 to 0.41)	+0.46 (0.11 to 1.04)
KeyMath	+0.28 (−0.14 to 0.70)	+0.16 (−0.27 to 0.58)	+0.12 (−0.29 to 0.53)	+1.29 (0.91 to 1.66)
Iowa	+0.14 (−0.28 to 0.56)	+0.24 (−0.19 to 0.66)	−0.10 (−0.51 to 0.31)	+0.85 (0.50 to 1.21)
Vanderbilt Story Problems	+0.79 (0.36 to 1.22)	+0.83 (0.39 to 1.28)	−0.04 (−0.45 to 0.37)	+0.62 (0.27 to 0.97)

Note. Effect sizes are based on unadjusted means at posttest and pooled standard deviation of both groups being compared. Effect sizes for difficulty status appear larger than suggested in Table 3 because significance (though not actual means) in Table 3 is adjusted for treatment group. Positive effect sizes indicate higher means for the first group named in the comparison. Values in parentheses are confidence intervals for the effect sizes. WPs = word problems; NCs = number combinations; MD = math difficulty; MDRD = math and reading difficulty.