. Author manuscript; available in PMC: 2012 Oct 1.

Published in final edited form as: J Nucl Med. 2011 Sep 8;52(10):1541–1549. doi: 10.2967/jnumed.111.091439

TABLE 3.

Linear Mixed Models with PET Measures as Outcome and Lesion Site, Disease Stage, and Number of Lesions (1–3, 4–6, or 7+) as Fixed Effects, with Random Patient Effects

Analysis	n	Estimate^*			$σ_{b}^{2}$ (between-patient variance)^†	$σ_{e}^{2}$ (within- patient variance)^†	$\frac{σ_{b}^{2}}{σ_{b}^{2} + σ_{e}^{2}}$ (ICC) ^†
Analysis	n	Bone	Lung	Soft tissue or lymph node	$σ_{b}^{2}$ (between-patient variance)^†	$σ_{e}^{2}$ (within- patient variance)^†	$\frac{σ_{b}^{2}}{σ_{b}^{2} + σ_{e}^{2}}$ (ICC) ^†
Analysis
¹⁸F-fluoroestradiol mean SUV_LBM	505	1.07 (0.83–1.38)	0.95 (0.64–1.41)	0.79 (0.61–1.04)	0.73	0.49	0.60 (0.50–0.69)
¹⁸F-FDG maximum SUV_LBM	492	2.88 (2.43–3.40)	2.01 (1.50–2.70)	2.32 (1.94–2.78)	0.30	0.25	0.54 (0.44–0.64)
¹⁸F-fluoroestradiol maximum /¹⁸F-FDG maximum ratio	492	0.74 (0.57–0.93)	0.69 (0.43–0.99)	0.66 (0.49–0.86)	0.06	0.03	0.65 (0.56–0.73)

With alternate PET measures
¹⁸F-fluoroestradiol maximum SUV_LBM	505	1.92 (1.57–2.34)	1.38 (1.00–1.90)	1.42 (1.15–1.75)	0.43	0.33	0.57 (0.47–0.66)
¹⁸F-fluoroestradiol mean SUV	505	1.60 (1.23–2.08)	1.39 (0.92–2.10)	1.16 (0.88–1.54)	0.80	0.51	0.61 (0.51–0.70)
¹⁸F-fluoroestradiol maximum SUV	505	2.88 (2.33–3.55)	2.02 (1.45–2.80)	2.11 (1.69–2.63)	0.50	0.33	0.60 (0.51–0.69)
¹⁸F-FDG maximum SUV	492	4.31 (3.62–5.13)	2.92 (2.17–3.94)	3.44 (2.86–4.14)	0.33	0.25	0.56 (0.46–0.66)

Transformed from log2 (¹⁸F-fluoroestradiol, ¹⁸F-FDG) or square root (ratio) scale used in model.

^†

Log2 (¹⁸F-fluoroestradiol, ¹⁸F-FDG) or square root (ratio) scale.

Data in parentheses are 95% CIs. Estimates shown are for patients with advanced disease and 1–3 lesions.