Table 2. Intra-day and inter-day accuracy and precision of LTE4 assay using calibration standards or pooled spiked urine from asthmatic children.

Intra- and inter-day analyses were conducted over a six-day period using either calibration standards or spiked, pooled urine from asthmatic children. Calibration spike standards were prepared in 30:70 Water:Methanol in 0.08% acetic acid and 0.04% ammonium hydroxide. Standards were then spiked into HPLC water and pooled urine from asthmatics at the indicated concentrations before analysis. Individual results were averaged and coefficient of variation (CV) and percent recovery (%R) were determined. Abbreviations: Average (AVG), Percent recovery (%R).

Calibration standards	Intra-day Accuracy and Precision (n=6)			Inter-day Accuracy and Precision (n=6)
(pg/mL)	AVG	CV	%R	AVG	CV	%R
5	5.35	15.90	107.07	5.25	11.52	104.92
10	10.11	9.82	101.07	9.77	11.28	97.74
25	24.13	2.59	96.52	24.77	11.69	99.09
50	49.26	7.01	98.52	50.32	5.84	100.64
100	98.66	1.69	98.66	99.35	4.43	99.35
250	238.32	4.00	95.33	244.26	2.18	97.71
500	514.17	3.11	102.83	506.66	1.38	101.33
Spiked urine	Intra-day Accuracy and Precision (n=6)			Inter-day Accuracy and Precision (n=6)
(pg/mL)	AVG	CV	%R	AVG	CV	%R
+0	81.09	4.59	NA	82.62	10.20	NA
+25	111.31	6.84	120.87	106.16	9.53	94.15
+50	132.11	6.08	102.04	131.67	5.30	98.09
+100	184.98	4.34	103.90	180.31	4.52	97.69
+250	322.11	6.72	96.41	317.71	8.43	94.04
+500	571.85	2.17	98.15	584.47	7.31	100.37