Table 2.
Regression model results comparing Yoga and HLW on primary and secondary outcomes.
| Parameter Estimate | 95% confidence interval | SE | p | |
|---|---|---|---|---|
| Depression Symptoms (QIDS) | ||||
|
| ||||
| Baseline Depression Symptoms (QIDS) | 0.74 | (0.54, 0.94) | 0.10 | 0.00 |
| Gender: Female vs Male | −0.50 | (−1.99, 1.00) | 0.76 | 0.51 |
| Age | 0.06 | (0.02, 0.10) | 0.02 | 0.01 |
| Baseline Physical Activity (IPAQ) | 0.43 | (−0.08, 0.93) | 0.26 | 0.10 |
| General Health Perceptions (SF-20) | −0.03 | (−0.05, −0.01) | 0.01 | 0.00 |
| Month of Assessment | −0.05 | (−0.09, −0.02) | 0.02 | 0.00 |
| Group: Yoga vs HLW | −1.42 | (−2.42, −0.43) | 0.51 | 0.01 |
|
| ||||
| Depression Symptoms (PHQ-9) | ||||
|
| ||||
| Baseline PHQ-9 | 0.38 | (0.23, 0.52) | 0.07 | 0.00 |
| Gender: Female vs Male | −1.54 | (−3.39, 0.30) | 0.94 | 0.10 |
| Age | 0.01 | (−0.05, 0.06) | 0.03 | 0.80 |
| Baseline Physical Activity (IPAQ) | 0.00 | (−0.63, 0.63) | 0.32 | 1.00 |
| General Health Perceptions (SF-20) | −0.04 | (−0.07, −0.02) | 0.01 | 0.00 |
| Month of Assessment | −0.05 | (−0.09, −0.01) | 0.02 | 0.01 |
| Group: Yoga vs HLW | −1.94 | (−3.20, −0.68) | 0.64 | 0.00 |
|
| ||||
| Getting Along with People (WHO-DAS) | ||||
|
| ||||
| Baseline Getting Along with People (WHO-DAS) | 0.59 | (0.45, 0.74) | 0.07 | 0.00 |
| Gender: Female vs Male | −0.69 | (−2.25, 0.86) | 0.79 | 0.38 |
| Age | 0.03 | (−0.02, 0.07) | 0.02 | 0.26 |
| Baseline Physical Activity (IPAQ) | 0.45 | (−0.05, 0.95) | 0.25 | 0.08 |
| General Health Perceptions (SF-20) | −0.03 | (−0.05, −0.01) | 0.01 | 0.02 |
| Month of Assessment | 0.02 | (−0.03, 0.06) | 0.02 | 0.47 |
| Group: Yoga vs HLW | −1.43 | (−2.46, −0.39) | 0.52 | 0.01 |
|
| ||||
| Life Activities (WHO-DAS) | ||||
|
| ||||
| Baseline Life Activities (WHO-DAS) | 0.30 | (0.11, 0.50) | 0.10 | 0.00 |
| Gender: Female vs Male | −0.12 | (−3.23, 2.99) | 1.55 | 0.94 |
| Age | 0.09 | (−0.01, 0.20) | 0.05 | 0.08 |
| Baseline Physical Activity (IPAQ) | 0.51 | (−0.46, 1.49) | 0.49 | 0.30 |
| General Health Perceptions (SF-20) | −0.05 | (−0.09, 0.00) | 0.02 | 0.05 |
| Month of Assessment | 0.05 | (−0.05, 0.14) | 0.05 | 0.36 |
| Group: Yoga vs HLW | −2.64 | (−4.73, −0.55) | 1.05 | 0.01 |
|
| ||||
| General Health Perceptions (SF-20) | ||||
|
| ||||
| General Health Perceptions (SF-20) | 0.71 | (0.61, 0.80) | 0.05 | 0.00 |
| Gender: Female vs Male | 6.14 | (−0.55, 12.83) | 3.40 | 0.07 |
| Age | −0.25 | (−0.45, −0.04) | 0.10 | 0.02 |
| Baseline Physical Activity (IPAQ) | 0.95 | (−1.45, 3.35) | 1.22 | 0.44 |
| Month of Assessment | −0.16 | (−0.28, −0.04) | 0.06 | 0.01 |
| Group: Yoga vs HLW | 7.27 | (2.54, 12.00) | 2.41 | 0.00 |
|
| ||||
| Physical Pain (SF-20) | ||||
|
| ||||
| Baseine Physical Pain (SF-20) | 0.47 | (0.36, 0.58) | 0.06 | 0.00 |
| Gender: Female vs Male | −4.25 | (−11.62, 3.13) | 3.75 | 0.26 |
| Age | −0.24 | (−0.46, −0.03) | 0.11 | 0.03 |
| Baseline Physical Activity (IPAQ) | 1.40 | (−1.35, 4.14) | 1.39 | 0.32 |
| General Health perceptions (SF-20) | 0.24 | (0.13, 0.36) | 0.06 | 0.00 |
| Month of Assessment | −0.20 | (−0.34, −0.05) | 0.07 | 0.01 |
| Group: Yoga vs HLW | 2.79 | (−2.19, 7.78) | 2.54 | 0.27 |
|
| ||||
| Physical Functioning (SF-20)a | ||||
|
| ||||
| Baseline Physical Functioning (SF-20) | 0.46 | (0.30, 0.61) | 0.08 | 0.00 |
| Gender: Female vs Male | 0.18 | (−0.21, 0.57) | 0.20 | 0.37 |
| Age | 0.17 | (0.02, 0.33) | 0.08 | 0.03 |
| Baseline Physical Activity (IPAQ) | −0.02 | (−0.17, 0.13) | 0.08 | 0.81 |
| General Health Perceptions (SF-20) | −0.29 | (−0.46, −0.13) | 0.08 | 0.00 |
| Month of Assessment | 0.01 | (0.01, 0.02) | 0.00 | 0.00 |
| Group: Yoga vs HLW | −0.10 | (−0.37, 0.17) | 0.14 | 0.47 |
Note. Because baseline is included as a covariate and NOT included as part of the dependent variable, the “Group: Yoga vs. HLW” parameter represents differences between groups at all non-baseline timepoints, adjusted for the baseline score. A statistically significant difference on this parameter indicates that the study arm (Yoga vs. HLW) has a significant impact on that outcome. We also tested models that included interactions between time and group for each of the outcome variables. These interaction terms were not statistically significant for any of the outcomes. Thus, the magnitude of the difference between groups was not statistically significantly different across the non-baseline timepoints.
IPAQ = International Physical Activity Questionnaire. PHQ-9 = Patient Health Questionnaire, 9 item. QIDS = Quick Inventory of Depression Symptomatology. SF-20 = 20-item Short-Form Survey. WHO-DAS = World Health Organization Disability Assessment Schedule.
For the physical functioning subscale, we reversed the scale (so that higher values = poorer functioning) prior to analysis in order to fit a negative binomial mixed effects model.