. Author manuscript; available in PMC: 2014 Aug 14.

Published in final edited form as: J Periodontol. 2009 Jul;80(7):1146–1153. doi: 10.1902/jop.2009.080654

Table 4.

Comparison of Within- and Between-Subject Variance for Samples

Assay	Within-Subject σ²	Between-Subject σ_α²	σ²/(σ² + σ_α²)
In-clinic
IL-1β	0.90 (95% CI: 0.77 to 1.04)	0.78 (95% CI: 0.56 to 1.11)	0.54
IL-6	0.72 (95% CI: 0.62 to 0.83)	1.03 (95% CI: 0.77 to 1.38)	0.41
TNF-α	1.03 (95% CI: 0.89 to 1.19)	0.65 (95% CI: 0.42 to 0.99)	0.61

At-home
IL-1β	1.03 (95% CI: 0.80 to 1.33)	0.70 (95% CI: 0.38 to 1.28)	0.60
IL-6	1.05 (95% CI: 0.81 to 1.35)	1.14 (95% CI: 0.77 to 1.67)	0.48
TNF-α	1.46 (95% CI: 1.13 to 1.88)	0.47 (95% CI: 0.06 to 3.32)	0.76

CI = confidence interval.