Chronic low back pain clinical outcomes present higher associations with the STarT Back Screening Tool than with physiologic measures: a 12-month cohort study

Table 2 Correlation coefficients between both the SBST^a and physiologic measures, and outcome variables at baseline

Variable	Disability	Pain intensity	Fear of movement
Prone endurance (s)	−0.26^*	−0.04	−0.22^*
Lateral endurance (s)	−0.11	0.07	−0.17
Prone MVC^b (N)	−0.36^*	−0.02	−0.11
Lateral MVC (N)	−0.11	−0.06	−0.02
Motor variability (cm)	−0.27^*	−0.04	−0.21
NMFslope^c (%S⁻¹)	0.14	−0.15	0.23^*
SBST score	0.43^**	0.12	0.40^**

Available paired data range from 53 down to 35, due to incomplete set of EMG data. Note that Kendall tau rank correlation coefficients are reported and that they are usually lower than Pearson r. Equivalence is determined by the formula r ≈ sin(π × τ/2) [38]
^*p < 0.05; ^**p < 0.001
^aSTarT Back Screening Tool
^bMaximal isometric voluntary contraction
^cNormalized median frequency slope

ISSN: 1471-2474