. Author manuscript; available in PMC: 2022 Apr 18.

Published in final edited form as: J Periodontol. 2020 Mar 16;91(10):1274–1283. doi: 10.1002/JPER.19-0457

TABLE 3.

Observed value difference and P value of salivary inflammatory mediators between groups of non-smokers, cigarette smokers, e-cig users, and dual smokers

Biomarkers	CS-NS	EC-NS	DS-NS	EC-CS	DS-CS	DS-EC
Cotinine (SD = 115)^a
Observed difference	142.05	179.65	298.40^*	37.61	156.36	118.75
P value	0.22	0.12	0.005	0.75	0.18	0.32
IL-1β (SD = 107)^a
Observed difference	65.83	−102.55	−117.02	−168.38	−182.85	−14.46
P value	0.56	0.36	0.28	0.11	0.08	0.89
PGE2 (SD = 92)^a
Observed difference	256.89^*	12.37	30.61	−244.52^*	−226.28^*	18.25
P value	0.004	0.90	0.73	0.006	0.01	0.84

CS-NS = CS group compared with NS; DS-CS = DS group compared with CS; DS-EC = DS group compared with EC; DS-NS = DS group compared with NS; EC-CS, EC group compared with CS; EC-NS, EC group compared with NS.

Standard deviation of null distributions for permutation tests. Under the null each difference has the same standard deviation.

P <0.01.