Table I.

Univariable and multivariable predictors of ADAMTS-4 in synovial fluid of the knee

	n∗	Median ADAMTS-4 ng/mL (IQR)	P-value†	Coefficient‡ (95% CI)	Concordancec (95% CI)	Nagelkerke'sR2 (95% CI)	P-value§
Univariable analysis
Age	170			0.08 (0.04–0.13)	0.69 (0.62–0.78)	0.10 (0.03–0.19)	<0.001
OA	159		<0.001		0.66 (0.59–0.73)	0.11 (0.04–0.22)	<0.001
No	118	0.0 (0–0.3)		2.4 (1.2–3.6)
Yes	41	1.3 (0–4.1)
Injury	160		0.10		0.58 (0.52–0.65)	0.03 (0.00–0.12)	0.10
None	32	0 (0–0)
Chondral	95	0 (0–2.2)		1.7 (0.2–3.3)
Other	33	0 (0–2.8)		1.4 (−0.4–3.3)
Effusion	122		<0.001‖		0.78 (0.69–0.86)	0.31 (0.17–0.49)	<0.001
No	71	0.0 (0.0–0.0)
Small	28	0.0 (0.0–0.75)		1.8 (0.4–3.2)
Moderate	14	1.7 (0.2–3.4)		3.6 (1.9–5.3)
Large	9	8.5 (4.0–12.3)		5.4 (3.4–7.3)
Inflammation	144		<0.001		0.68 (0.60–0.76)	0.11 (0.03–0.24)	<0.001
No	62	0.0 (0.0–0.0)
Yes	82	0.2 (0.0–2.8)		2.4 (1.1–3.6)
Multivariable analysis
Full model	104				0.88 (0.83–0.96)	0.46 (0.36–0.66)
Age		0.72¶	0.13¶	0.07
OA		0.65	0.10	0.64
Injury		0.54	0.01	0.86
Effusion		0.79	0.34	<0.001
Inflammation		0.70	0.15	0.04
Reduced model	106				0.88 (0.83–0.95)	0.46 (0.34–0.63)
Age		0.05 (0.01–0.09)	0.72¶	0.13¶	0.02
Effusion			0.79	0.34	<0.001
No
Small		1.7 (0.4–3.0)
Moderate		3.3 (1.7–4.8)
Large		4.4 (2.6–6.2)
Inflammation			0.71	0.16	0.006
No
Yes		1.8 (0.5–3.0)

Notes (IQR: interquartile range; CI: confidence intervals).

^∗Number of patients for each analysis, which vary due to data missingness.

^†P-values from univariate non-parametric statistical analyses.

^‡Coefficients from censored regression.

^§P-values from censored regression.

^‖P-value from Jonckheere trend test.

^¶Concordance and Nagelkerke's R² values for individual predictors in the full and reduced models are the univariable values when calculated using each model's dataset. They are therefore NOT partial concordance or R² coefficients.