Table 1.

Discriminative value of bone turnover status for non-vertebral fracture presence/prediction

Bone turnover status	Fracture site	OR	95%CI	AUC	Sensitivity, %	Specificity, %	PPV, %	NPV, %	Accuracy, %
1*.P1NP>32 µg/L, bCTX<0.250 µg/L, P1NP/ bCTX >100.0 (n=67)	Hip	0.43	0.19-0.97 (p=0.043)	0.7837	75.0	67.6	73.3	69.4	71.6
	Any fracture	0.77	0.46-1.30 (p=0.324)	0.6916	91.2	18.02	71.3	47.9	68.6
2A*. P1NP<32 µg/L, bCTX <0.250 µg/L, P1NP/ bCTX >100.0 (n=144)	Hip	0.70	0.43-1.14 (p=0.151)	0.7815	76.7	66.0	73.0	70.3	71.8
	Any fracture	0.73	0.50-1.06 (p=0.095)	0.6918	91.3	17.8	71.4	47.5	68.7
2B. P1NP<32 µg/L, bCTX <0.250 µg/L, P1NP/ bCTX <100.0 (n=57)	Hip	3.23	1.37-7.65 (p=0.008)	0.8061	66.7	84.9	76.9	77.1	71.0
	Any fracture	2.04	1.00-4.17 (p=0.051)	0.7220	82.3	39.4	69.9	56.5	66.4
3. P1NP<32 µg/L, bCTX >0.250 µg/L, P1NP/ bCTX >100.0 (n=272)	Hip	2.40	1.42-4.06 (p=0.001)	0.8124	79.0	70.1	77.0	72.5	75.1
	Any fracture	1.74	1.14-2.65 (p=0.010)	0.7194	89.9	27.9	74.0	54.7	71.0
4A. P1NP>32 µg/L, bCTX>0.250 µg/L, P1NP/ bCTX >100.0 (n=388)	Hip	0.94	0.58-1.53 (p=0.815)	0.7597	57.6	84.7	70.2	76.1	74.2
	Any fracture	0.94	0.66-1.34 (p=0.714)	0.6647	77.7	38.2	65.1	53.5	61.8
4B. P1NP>32 µg/L, bCTX >0.250 µg/L, P1NP/ bCTX <100.0 (n=295)	Hip	2.53	1.48-4.33 (p=0.001)	0.8247	81.2	72.8	79.1	75.4	77.5
	Any fracture	2.08	1.37-3.16 (p=0.001)	0.7412	91.4	26.5	75.2	55.7	72.5

The asterisk (^*) on the subtypes 1 and 2A indicates comparison with the rest of the cohort. For all other subtypes comparison was made with combined data for subtypes 1 and 2A.

Abbreviations: P1NP, N-terminal propeptide of type I procollagen; β-CTX, C-terminal βcross-linked telopeptide of type I collagen; HF, hip fracture; OR, odds ratio; AUC, area under the receiver operating characteristic curve; CI, confidence interval; PPV, positive predictive value; NPV, negative predictive value.