. Author manuscript; available in PMC: 2014 Mar 1.

Published in final edited form as: Dev Sci. 2012 Dec 8;16(2):234–248. doi: 10.1111/desc.12019

Table 4.

Mean (SD) of accuracy and reaction time (RT) in the looking-while-listening task at 18 and 24 months for all participants and the lower- and higher-SES sub-groups

	All participants	Lower SES	Higher SES
Accuracy^a
18 months	.64 (.09)^*	.59 (.08)^*	.69 (.07)^*
24 months	.73 (.10)^*	.69 (.11)^*	.77 (.08)^*
RT^b
18 months	841 (185)	947 (151)	746 (162)
24 months	738 (162)	802 (166)	666 (108)

Comparisons to chance (.50) are significant, all p < .001.

Mean proportion looking to the target computed over 300 to 1800 ms from noun onset, including all target-initial and distracter-initial trials on which the parent reported the child understood the target word.

Mean latency (ms) to initiate a shift from the distracter to the target picture within 300 to 1800 ms from noun onset including only those trials on which the parent reported the child understood the target word.