Table 3: Precision and accuracy of quality control samples (n=6).

Analyte	Nominal concentration (ng/ml)	Accuracy (Bias (%))			Precision (CV (%))
		Day 1	Day 2	Day 3	Day 1	Day 2	Day 3	Inter-day (n=18)
PGP	0.01	158.10	−18.57	35.10	11.76	41.40	27.14	64.11
	0.07	17.89	−2.73	7.03	7.91	16.75	18.68	19.89
	0.25	−22.68	−17.92	−16.76	8.07	8.05	14.61	16.15
	2.5	1.64	12.32	−0.60	5.39	12.39	10.87	12.26
	25	6.20	13.12	3.00	9.59	8.98	10.67	11.39
	50	13.42	14.10	0.32	6.47	8.66	10.81	10.53
AcPGP	0.01	−15.41	1.50	51.30	84.20	111.32	48.56	61.67
	0.07	15.77	−7.96	12.54	18.19	18.09	16.97	19.54
	0.25	6.00	−1.72	−2.20	6.80	11.58	6.96	12.27
	2.5	8.00	−3.56	−1.56	5.39	7.96	1.98	5.45
	25	10.36	−3.36	−5.64	2.00	4.61	4.76	6.56
	50	9.64	−4.38	−4.90	3.46	1.76	6.21	4.64