Mediators of Yoga and Stretching for Chronic Low Back Pain
Table 2
Associations between 6-week change in mediator values and intervention group#.
Main cohort*
Saliva cohort**
Change in mediator
SE
95% CI
value
Change in mediator
SE
95% CI
value
Yoga versus self-care
Fear avoidance
1.39
(−3.00, 2.52)
0.865
2.67
1.87
(−1.07, 6.41)
0.158
Self-efficacy
0.78
0.30
(0.19, 1.38)
0.010
0.63
0.37
(−0.10, 1.36)
0.090
Conscious awareness of body
1.29
1.24
(−1.16, 3.74)
0.299
1.51
(−3.41, 2.63)
0.796
Psychological distress
1.56
(−4.26, 1.92)
0.456
1.89
(−5.20, 2.36)
0.455
Perceived stress
1.02
(−2.24, 1.80)
0.828
1.32
(−2.77, 2.51)
0.922
Positive states of mind
0.51
0.51
(−0.50, 1.52)
0.316
0.48
0.59
(−0.70, 1.66)
0.418
Improved sleep
0.10
(−0.39, 0.00)
0.050
−0.20
0.13
(−0.45, 0.06)
0.131
Hours of back exercise
0.93
0.27
(0.41, 1.46)
0.0006
1.32
0.31
(0.70, 1.95)
0.00007
DHEA change in diurnal average (log scale)
—
—
—
—
0.19
0.13
(−0.06, 0.44)
0.139
Average cortisol awakening response (CAR)
—
—
—
—
−0.12
0.27
(−0.66, 0.42)
0.658
Stretching versus self-care
Fear avoidance
1.26
(−4.23, 0.77)
0.173
1.56
(−3.16, 3.09)
0.981
Self-efficacy
0.84
0.26
(0.32, 1.36)
0.002
0.75
0.36
(0.03, 1.48)
0.042
Conscious awareness of body
0.76
1.49
(−2.18, 3.71)
0.608
1.82
(−4.85, 2.41)
0.505
Psychological distress
1.62
(−5.27, 1.16)
0.207
2.07
(−4.30, 3.96)
0.934
Perceived stress
0.86
(−3.05, 0.37)
0.122
1.12
(−2.35, 2.14)
0.926
Positive states of mind
0.64
0.45
(−0.25, 1.52)
0.156
0.64
0.55
(−0.45, 1.73)
0.247
Improved sleep
0.10
(−0.27, 0.12)
0.448
0.13
(−0.30, 0.22)
0.765
Hours of back exercise
1.25
0.23
(0.79, 1.71)
0.000001
1.72
0.30
(1.13, 2.32)
0.0000002
DHEA change in diurnal average (log scale)
—
—
—
—
0.08
0.15
(−0.21, 0.37)
0.595
Average cortisol awakening response (CAR)
—
—
—
—
0.07
0.28
(−0.50, 0.64)
0.799
Each mediator is an outcome variable in a model with intervention as the predictor variable and adjustment for selected baseline variables. Therefore, note that effect size comparison across rows should not be done since outcome variable is changing. Adjusted for baseline variables age, sex, BMI, back pain days, work type, pain travelling down the leg, bothersomeness, and RDQ. Same adjustments as main cohort analysis with the addition of alcohol, tobacco, and medication use on the day of saliva sample collection.
