. Author manuscript; available in PMC: 2013 Jan 1.

Published in final edited form as: Sci Stud Read. 2012 Jan 9;16(5):457–474. doi: 10.1080/10888438.2011.599902

Table 1.

Means (and Standard Deviations) for Decoding-related Measures for the Total Sample and by Zygosity

	Total Sample N=2,504	MZ N=854	DZ N=1,650	MZ vs. DZ t (2,502)
Letter Naming Fluency	52.39 (17.92)	51.28 (17.53)	52.97 (18.09)	−2.24
Phoneme Segmentation Fluency	40.07 (17.03)	38.97 (17.47)	40.64 (16.78)	−2.33
Nonsense Word Fluency	43.93 (24.91)	42.23 (23.95)	44.81 (25.35)	−2.46^*

Note: Ns are for individuals. Independent samples t-tests are reported for the comparison between MZ and DZ twins. Variances did not differ significantly between MZ and DZ twins for any measure.

p = .014.