The study compared a group of 35 states which scored at or above the national mean on the 2003 fourth grade NAEP reading assessment with a group of 13 states which scored below the national NAEP mean. There were substantial differences between the two groups on most of the eight predictor variables. The two groups of states were also compared on the 2015 NAEP fourth grade reading assessment. The differences which existed between the two groups in 2003 also were found in 2015. For the most part the rank order of the total group of 48 states in 2015 was quite similar to the rank order in 2003. The correlation between state reading scores in 2003 and state reading scores in 2015 was 0.82.
Smith, Stuart E., "Eleven of the 13 States Scored Below the National NAEP Reading Mean in 2003 Scored Below in 2015" (2017). NERA Conference Proceedings 2017. 10.