Dual energy x-ray absorptiometry analysis contributes to the prediction of hip osteoarthritis progression

Table 4 Models using clinical, radiological and DXA variables

	Variables	% Diff. & p	-2 Log	R²	AIC	AUC	TNR	TPR
1	KL score affected side:	30.7% (***)	159.5	0.31	163.5	0.76	93.2	37.2
2	DXA affected side:		184.2	0.15	192.2	0.69	97.3	9.3
	- BMC medial part femoral head	13.9% (***)
	- BMC inferior part femoral head	7.2% (***)
	- BMC femoral neck	5%(*)
3	DXA affected side + KL:		148.6	0.38	158.6	0.83	93.9	34.9
	- BMC medial part femoral head	13.9%(*)
	- BMC inferior part femoral head	7.2%(*)
	- BMC femoral neck	5%(**)
	- KL affected side	NA(***)
4	KL affected side + Delta KL		154.0	0.35	160	0.82	93.9	34.9
	- KL score affected side	NA(***)
	- Delta KL	32%(*)
5	DXA ROI'S difference:		135.6	0.45	153.6	0.84	91.7	51.2
	- Difference superior area fem head	16.5% (*)
	- Difference trochanteric area size	2% (*)
	- Difference BMD sup. part fem. head	5.7% (**)
	- Difference BMC sup. part fem. head	9% (**)
	- Difference BMD med. part fem. head	4.6% (**)
	- Difference BMC med. part fem. head	4% (**)
	- Difference Intertrochanteric area size	-4.5% (*)
	- KL score affected side	NA(***)

The difference in values between affected hip and contralateral side is expressed in percentage (%). Positive values represent an increase in the affected hip. No applicable (NA) in the cases that the variable only reflect the affected side. Level of significance codes: '***' P value < 0.001, '**' P value < 0.01, '*' P value < 0.05. All models were corrected for patient characteristics. TPR and TNR columns correspond to the percentage correctly predicted by the models. *Area under the curve value obtained after 10-fold cross validation process.
AIC = An Information Criterion; AUC = areas under the curve; DXA = dual energy X-ray absorptiometry; KL = Kellgren and Lawrence score of the affected side; ROI = rate opf interest; TNR = true negative rate TPR = true positive rate