Table 2.

Mean puffing patterns, product use, subjective effects and biomarker levels across the four conditions.

	6 mg/ml fixed power		18 mg/ml fixed power		6 mg/ml adjustable power		18 mg/ml adjustable power		Nicotine	Power	Nicotine × power
	Mean	SD	Mean	SD	Mean	SD	Mean	SD	F (P)	F (P)	F (P)
Puffing topography
Daily puff number	338	161	279	127	308	135	272	128	16.39 (0.001)	2.16 (0.16)	0.98 (0.34)
Puff duration	4.46	1.22	3.61	0.97	3.81	1.11	3.91	1.44	18.30 (0.001)	1.69 (0.21)	12.12 (0.003)
Interpuff interval	34.22	20.08	41.22	26.23	39.32	26.80	37.32	27.18	0.33 (0.58)	0.04 (0.86)	5.76 (0.03)
Product use
Daily (ml) liquid consumed	6.19	3.74	4.63	2.13	5.79	3.63	4.79	2.35	6.25 (0.02)	0.07 (0.80)	0.75 (0.40)
Voltage (wattage)	4 (10)	–	4 (10)	–	4.5 (12.66)	0.7	4.3 (11.56)	0.8	–	–	–
Subjective effects
Urge to vape	3.20	1.11	2.40	0.10	3.00	0.86	2.45	0.83	16.74 (0.001)	0.77 (0.39)	1.95 (0.18)
Strength of urges	2.90	1.17	2.15	0.67	2.85	1.18	2.45	1.10	14.63 (0.001)	0.91 (0.36)	3.56 (0.08)
Withdrawal symptoms	9.05	4.56	7.80	2.59	7.45	2.91	6.80	1.36	4.88 (0.04)	8.78 (0.01)	2.51 (0.13)
Positive effects	50.71	19.82	62.64	20.30	63.85	21.58	63.42	22.25	2.06 (0.17)	4.69 (0.05)	26.48 (0.001)
Negative effects	15.05	19.49	22.25	22.75	11.26	9.66	14.74	12.84	3.37 (0.09)	5.36 (0.03)	0.38 (0.55)
Biomarkers
Salivary cotinine (ng/ml)	250.45	188.23	402.52	190.00	274.95	172.81	405.21	192.80	17.49 (0.001)	0.15 (0.70)	0.12 (0.73)
3‐HPMA (ng/mg creatinine)	211.83	133.09	262.73	202.50	224.13	343.39	378.35	467.35	0.82 (0.38)	0.29 (0.60)	0.09 (0.77)
Formate (μg/mg creatinine)	10.52	8.00	9.62	7.28	18.01	23.56	7.61	7.24	4.58 (0.05)	1.88 (0.19)	6.92 (0.02)

SD = standard deviation; 3‐HPMA = 3‐hydroxypropylmercapturic acid.