Table 3.

Comparison of cumulative lead exposure determined by expert assessment with exposure determined by a job exposure matrix for meningioma cases and controls in the NCI Brain Tumor Study

	Overall						ALAD1						ALAD2
	Expert						Expert						Expert
	JEM	0	1	2	3	U	JEM	0	1	2	3	U	JEM	0	1	2	3	U
	0*	364	70	42	8	4	0	298	58	34	6	4	0	66	12	8	2	0
	1*	10	12	13	1	0	1	9	12	11	0	0	1	1	0	2	1	0
	2*	18	37	29	9	1	2	13	32	23	6	1	2	5	5	6	3	0
	3*	0	7	13	10	0	3	0	5	11	9	0	3	0	2	2	1	0
	U*	4	1	1	1	1	U	2	1	0	0	1	U	2	0	1	1	0
Sensitivity†	0.49						0.49						0.48
Specificity†	0.88						0.88						0.87
% agreement	63						64						61
Kappa	0.29						0.30						0.24
w-Kappa‡	0.42						0.43						0.37

^*0 = no exposure, 1 = ≤to 80^th percentile, 2 = >80^th to 95^th percentile, 3 = >95^th percentile, U = unknown

^†Classified as 2 or 3; restricted to non-missing data

^‡Weighted Cohen’s Kappa (single category difference in agreement given weight of 0.66 and two category difference in agreement given weight of 0.33); restricted to non-missing data