. Author manuscript; available in PMC: 2013 Apr 18.

Published in final edited form as: J Spec Educ. 2008 Sep 17;43(4):236–254. doi: 10.1177/0022466908323007

Table 3.

Estimated Effects of Special Education Services on Children’s Reading and Mathematics Skills

	OLS Regression (no covariates)	OLS Regression (covariates)	Stratification Matching	Nearest Neighbor Matching	Kernel Matching
2004 Reading IRT Test scores	−22.276^***	−6.622^***	−3.995^**	−2.872	−3.514^*
2002–2004 Reading IRT Test score gains	2.772^***	.789	1.080	.955	.802
2004 grade IRT Math Test scores	−16.415^***	−3.350^***	−1.732	−2.161	−1.704
2002–2004 IRT Math Test score gains	−.351	−.693	−.574	−.617	−.389

p<.05;

^**

p<.01;

^***

p<.001