Table 4.

Analytical recovery and imprecision data for cannabinoids and cannabinoid glucuronides in human urine by liquid chromatography tandem mass spectrometry

		Analytical recovery				Imprecision
		(% of expected concentration)				(% coefficient of variation, N= 20)
		Intra-day, N=4		Inter-day, N=20
	Concentration					Pooled
	(ng/ml)	Mean	Range	Mean	Range	Intra-day	Inter-day	Total
	6	99.0	91.7–112.3	99.0	88.2–112.3	5.7	1.4	5.9
THC	25	97.7	85.2–104.8	96.7	81.2–118.0	10.2	0	10.2
	75	97.5	87.1–111.2	94.7	80.5–111.2	8.6	0	8.6
	2.5	97.9	85.6–108.0	101.3	85.6–108.0	4.7	0	4.7
11-OH-THC	25	96.5	94.4–98.4	100.4	94.4–111.2	3.0	2.6	3.9
	75	91.5	89.3–93.7	97.3	89.3–103.5	2.6	3.3	4.2
	2.5	87.7	83.6–90.8	92.8	83.2–102.0	4.1	3.6	5.5
THCCOOH	25	89.5	88.0–91.6	92.9	84.4–104.4	3.2	4.7	5.6
	75	88.1	85.5–90.1	93.0	85.5–102.0	2.6	4.0	4.7
	2.5	97.1	90.0–113.6	98.1	81.6–116.8	7.9	5.6	9.7
Cannabidiol	25	109.0	103.2–113.6	100.5	85.2–114.8	6.5	4.8	8.1
	75	95.5	88.1–102.9	98.3	81.2–118.0	6.9	4.8	8.4
	6	95.3	82.7–108.3	97.9	82.7–115.0	6.9	3.9	7.9
Cannabinol	25	98.9	91.6–107.2	94.8	81.2–114.0	9.6	0	9.6
	75	93.5	87.6–99.5	93.1	83.1–113.5	8.0	0	8.0
	1.5	93.2	88.0–97.3	96.1	88.0–102.7	3.0	0	3.0
THC-glucuronide	15	95.2	90.7–100.7	100.1	90.7–112.0	2.8	4.4	5.2
	45	98.1	95.8–102.7	101.0	93.3–111.1	3.1	3.8	4.9
	7.5	85.0	82.9–87.9	88.7	82.0–97.5	3.1	3.7	4.8
THCCOOH- glucuronide	75	88.3	83.7–93.6	92.4	83.7–101.3	3.0	3.7	4.7
	225	90.8	87.6–92.4	90.7	83.6–98.2	3.2	1.9	3.7

THC= Δ9-tetrahydrocannabinol, 11-OH-THC= 11-hydroxy-THC, THCCOOH= 11-nor-9-carboxy-THC.