Table 3.

Parameter estimates and p-values from multiple regression analyses examining the differences between the low and high exposure groups for each of the neurobehavioral outcome measures. Negative differences correspond to poorer performance of the high exposed group compared to the low exposed group, while positive differences indicate the opposite. Items in bold indicate the high exposed group performed significantly worse than the low exposed group.

Test measure	Low exposure versus high exposure
	Parameter estimate	t-statistic	DF	p-value
Tapping: right hand	−1564	2.47	91	.02a,b
Tapping: left hand	−1506	2.46	91	.02a,b
Tapping: alternating hands	−273	.50	91	.62
Reaction Time	−4299	1.55	91	.12a
Trail Making: part A	−1089	2.24	50	.03
Trail Making: part B	−2863	3.22	50	.002
Symbol Digit	−8648	−.22	90	.83
Similarities	−304	1.75	50	.09b
Benton Visual Retention	−27	.29	50	.77b
Serial Digit Learning: score	57	−.82	90	.42b
Serial Digit Learning: number of trials	−59	−.65	90	.52b
Digit Span: forward	−36	.67	91	.51b
Digit Span: reverse	0	−.004	91	.99
Selective Attention: latency	4033	.19	90	.85
Selective Attention: median inter-stimulus interval	41290	−1.23	90	.22
Selective Attention: number of trials	−9712	2.42	90	.02
Block Design	−62	.32	50	.75b
Visual Motor Integration	−172	1.48	50	.14b
Santa Ana: dominant hand	−998	2.67	50	.01b
Santa Ana: non-dominant hand	−630	2.31	50	.02b
Reversal Learning: time to learn	2011	.51	90	.61
Reversal Learning: time to reverse	813	.22	90	.82

^ap < .05 for an education difference for the given test outcome.

^bp < .05 for a field station difference for the given test outcome.