Table 4.

Sensitivity, specificity, PPV, NPV, LR+ and LR− for STarT-Back and 9APSI criteria to identify high- and low-risk patients in the STarT-Back validation and the POP samples using available definitions for a poor outcome.

	SBSTa		9APSI-POP
Poor outcome definition	RMDQ ≥7 at 6 months		RMDQ ≥7 at 6 months		Perceived non-recovery and ≥3 pain at 6 months		RMDQ ≥7 at 2 years		Grade 2 Von Korff at 2 years		Perceived non-recovery and ≥3 pain at 2 years
Risk group	H versus L/M	H/M versus L	H versus L/M	H/M versus L	H versus L/M	H/M versus L	H versus L/M	H/M versus L	H versus L/M	H/M versus L	H versus L/M	H/M versus L
Sensitivity	29.6%*	80.1%	32.1%	81.7%	27.5%	76.8%	36.6%	77.1%	21.2%	80.7%	25.9%	73 8%
Specificity	94.6%	65.4%	80.1%	37.8%	82.3%	35.1%	77.6%	39.4%	81.5%	38.5%	83.5%	36.8%
PPV	78.4%	60.4%	29.6%	27.6%	25.9%	16.4%	28.6%	30.0%	21.7%	23.6%	28.6%	20.7%
NPV	67.1%	83.3%	82.0%	87.8%	83.5%	90.7	83.3%	83.7%	81.0%	89.5%	82.3%	86.2%
LR+	5.48	2.32	1.61	1.31	1.55	1.18	1.63	1.27	1.15	1.31	1.57	1.17
LH−	0.74	0.30	0.85	0.48	0.88	0.66	0.82	0.58	0.97	0.50	0.89	0.71

9APSI, Nine Analogous Predictive Screening Items; H, high risk; L, low risk according to STarT-Back criteria; LH−, negative likelihood ratio; LR+, positive likelihood ratio; M, medium risk; NPV, negative predictive value; POP, Prognosis of Pain study sample; PPV, positive predictive value; RMDQ, Roland–Morris Disability Questionnaire.

^*The value of 39.6% in Table 4 by Hill et al. (2008) may be a typo, as we recalculated all values using the numbers provided in the text on page 638: 58 of 196 are 29.6% participants with RMDQ score ≥7.

^aSix individuals were not accounted for reducing the sample size with complete data to 494.