Table 2.
Univariate and multivariate comparisons of change from baseline scores between groups (weeks 8 and 12)
| Descriptive statistics using raw data | Change from baseline using linear mixed-effects modela | ||||||
|---|---|---|---|---|---|---|---|
| Baseline | Week 8 | Week 12 | Week 8 | Week 12 | |||
| Mean (SD) | Mean (SD) | Mean (SD) | Adj. mean (CI 95 %) | p value | Adj. mean (CI 95 %) | p value | |
| PSS | |||||||
| CTL | 22.3 (7.1) | 18.8 (7.6) | 18.9 (7.3) | −3.46 (−4.48, −2.43) | <0.0001 | −3.43 (−4.47, −2.40) | <0.0001 |
| ISM | 22.4 (7.1) | 17.2 (6.0)b | 16.0 (6.4)b | ||||
| ISM+ | 22.4 (6.1) | 15.4 (5.9)b | 15.1 (7.0)b | ||||
| ISM vs. CTL | −1.73 (−3.39, −0.06) | 0.043 | −2.92 (−4.68, −1.16) | 0.001 | |||
| ISM+ vs. CTL | −3.21 (−4.83, −1.58) | 0.0001 | −3.39 (−5.07, −1.70) | <0.0001 | |||
| MAAS | |||||||
| CTL | 3.29 (0.90) | 3.65 (0.89) | 3.68 (0.96) | 0.35 (0.24, 0.47) | <0.0001 | 0.40 (0.28, 0.52) | <0.0001 |
| ISM | 3.45 (0.89) | 4.03 (0.80)b | 4.02 (0.82)b | ||||
| ISM+ | 3.24 (0.80) | 3.86 (0.82)b | 3.98 (0.84)b | ||||
| ISM vs. CTL | 0.23 (0.03, 0.42) | 0.022 | 0.22 (0.01, 0.42) | 0.037 | |||
| ISM+ vs. CTL | 0.23 (0.05, 0.42) | 0.015 | 0.34 (0.14, 0.53) | 0.0007 | |||
| ASTI | |||||||
| CTL | 27.4 (4.6) | 29.0 (5.4) | 29.4 (4.8) | 1.57 (0.75, 2.38) | 0.0002 | 1.95 (1.12, 2.77) | <0.0001 |
| ISM | 27.7 (4.8) | 31.5 (4.3)b | 31.1 (4.8)b | ||||
| ISM+ | 27.2 (4.9) | 30.8 (4.7)b | 31.9 (5.8)b | ||||
| ISM vs. CTL | 2.21 (0.89, 3.54) | 0.001 | 1.50 (0.11, 2.90) | 0.035 | |||
| ISM+ vs. CTL | 2.07 (0.78, 3.37) | 0.002 | 2.79 (1.46, 4.13) | <0.0001 | |||
| PWB-SA | |||||||
| CTL | 57.9 (13.2) | 59.5 (12.9) | 59.5 (13.3) | 1.54 (0.12, 2.96) | 0.034 | 2.10 (0.66, 3.53) | 0.004 |
| ISM | 57.1 (14.0) | 62.3 (11.9)b | 61.2 (13.5)b | ||||
| ISM+ | 56.5 (11.7) | 62.4 (11.7) b | 63.7 (12.5)b | ||||
| ISM vs. CTL | 3.73 (1.42, 6.04) | 0.002 | 2.97 (0.53, 5.41) | 0.017 | |||
| ISM+ vs. CTL | 4.14 (1.88, 6.39) | 0.0004 | 4.57 (2.23, 6.91) | 0.0001 | |||
| SVS | |||||||
| CTL | 27.4 (9.1) | 29.1 (9.3) | 29.1 (9.7) | 1.73 (0.67, 2.79) | 0.001 | 1.70 (0.63, 2.77) | 0.002 |
| ISM | 28.0 (8.9) | 31.1 (8.2) | 31.7 (9.4) | ||||
| ISM+ | 28.1 (9.4) | 32.5 (9.1)b | 32.4 (9.3)b | ||||
| ISM vs. CTL | 1.41 (−0.31, 3.13) | 0.11 | 2.06 (0.24, 3.88) | 0.027 | |||
| ISM+ vs. CTL | 2.65 (0.97, 4.33) | 0.002 | 2.54 (0.80, 4.28) | 0.005 | |||
| SF-36 | |||||||
| Physical function | |||||||
| CTL | 83.5 (21.9) | 85.8 (18.5) | 87.1 (18.5) | 2.01 (−0.25, 4.27) | 0.082 | 2.40 (0.10, 4.69) | 0.041 |
| ISM | 81.7 (26.4) | 83.5 (23.0) | 84.5 (21.7) | ||||
| ISM+ | 84.1 (21.6) | 86.1 (16.9) | 85.9 (19.7) | ||||
| ISM vs. CTL | −0.50 (−4.18, 3.19) | 0.79 | −0.78 (−4.67, 3.11) | 0.70 | |||
| ISM+ vs. CTL | −0.02 (−3.61, 3.57) | 0.99 | −2.11 (−5.84, 1.61) | 0.27 | |||
| Role physical | |||||||
| CTL | 68.9 (39.7) | 73.1 (38.7) | 71.9 (39.5) | 4.17 (−2.41, 10.8) | 0.21 | 2.97 (−3.69, 9.63) | 0.38 |
| ISM | 70.5 (41.1) | 80.5 (32.2) | 80.8 (32.4) | ||||
| ISM+ | 73.2 (38.4) | 79.9 (36.2) | 79.9 (34.6) | ||||
| ISM vs. CTL | 5.82 (−4.89, 16.5) | 0.29 | 7.39 (−3.88, 18.7) | 0.20 | |||
| ISM+ vs. CTL | 2.46 (−7.98, 12.9) | 0.64 | 3.73 (−7.07, 14.5) | 0.50 | |||
| Bodily pain | |||||||
| CTL | 69.9 (24.6) | 73.6 (23.9) | 71.8 (24.8) | 3.26 (−0.08, 6.61) | 0.056 | 1.71 (−1.67, 5.09) | 0.32 |
| ISM | 70.1 (27.3) | 76.5 (20.9) | 78.9 (24.5) | ||||
| ISM+ | 69.6 (23.0) | 74.6 (22.6) | 74.5 (22.4) | ||||
| ISM vs. CTL | 3.04 (−2.40, 8.48) | 0.27 | 5.72 (−0.01, 11.5) | 0.051 | |||
| ISM+ vs. CTL | 1.58 (−3.73, 6.89) | 0.56 | 3.09 (−2.41, 8.59) | 0.27 | |||
| General health | |||||||
| CTL | 65.4 (21.3) | 67.1 (21.7) | 66.8 (22.9) | 1.51 (−0.69, 3.71) | 0.18 | 2.27 (0.04, 4.50) | 0.046 |
| ISM | 64.7 (24.8) | 69.2 (23.3) | 68.8 (24.5) | ||||
| ISM+ | 67.8 (21.2) | 73.2 (18.7)b | 74.6 (19.5) | ||||
| ISM vs. CTL | 2.97 (−0.61, 6.55) | 0.10 | 0.63 (−3.16, 4.41) | 0.75 | |||
| ISM+ vs. CTL | 3.18 (−0.32, 6.67) | 0.075 | 2.49 (−1.13, 6.12) | 0.18 | |||
| Vitality | |||||||
| CTL | 42.8 (22.8) | 46.8 (23.4) | 47.7 (24.0) | 4.05 (1.17, 6.94) | 0.006 | 4.92 (2.00, 7.84) | 0.001 |
| ISM | 44.7 (23.3) | 53.8 (22.2)b | 54.0 (24.6) | ||||
| ISM+ | 43.2 (22.8) | 57.7 (21.8)b | 56.9 (23.2)b | ||||
| ISM vs. CTL | 5.11 (0.42, 9.80) | 0.033 | 4.37 (−0.59, 9.33) | 0.085 | |||
| ISM+ vs. CTL | 10.4 (5.81, 15.0) | <0.0001 | 8.79 (4.04, 13.5) | 0.0003 | |||
| Social function | |||||||
| CTL | 67.4 (25.9) | 72.0 (25.9) | 73.1 (26.2) | 4.65 (0.69, 8.61) | 0.022 | 5.74 (1.73, 9.74) | 0.005 |
| ISM | 66.1 (28.6) | 79.0 (22.2)b | 79.3 (23.2) | ||||
| ISM+ | 70.5 (25.9) | 83.4 (22.9)b | 84.8 (19.1)b | ||||
| ISM vs. CTL | 8.21 (1.77, 14.7) | 0.013 | 7.44 (0.65, 14.2) | 0.032 | |||
| ISM+ vs. CTL | 8.27 (1.99, 14.6) | 0.010 | 8.59 (2.09, 15.1) | 0.010 | |||
| Role emotional | |||||||
| CTL | 49.5 (40.1) | 62.1 (40.4) | 59.2 (40.2) | 11.6 (4.42, 18.7) | 0.002 | 9.48 (2.24, 16.7) | 0.011 |
| ISM | 54.7 (42.6) | 68.0 (34.4) | 74.3 (34.6) | ||||
| ISM+ | 57.9 (40.9) | 73.8 (35.9) | 78.6 (35.0) | ||||
| ISM vs. CTL | 2.37 (−9.28, 14.0) | 0.69 | 11.5 (−0.73, 23.8) | 0.066 | |||
| ISM+ vs. CTL | 3.74 (−7.61, 15.1) | 0.52 | 7.70 (−4.04, 19.4) | 0.20 | |||
| Mental health | |||||||
| CTL | 56.7 (19.4) | 62.0 (19.8) | 61.2 (19.9) | 4.89 (2.16, 7.63) | 0.0005 | 4.69 (1.92, 7.45) | 0.001 |
| ISM | 57.1 (20.6) | 69.5 (16.8)b | 66.8 (19.5)b | ||||
| ISM+ | 58.1 (18.6) | 71.2 (18.3)b | 72.1 (20.2)b | ||||
| ISM vs. CTL | 7.43 (2.98, 11.9) | 0.001 | 5.63 (0.93, 10.3) | 0.019 | |||
| ISM+ vs. CTL | 7.47 (3.13, 11.8) | 0.0008 | 8.36 (3.86, 12.9) | 0.0003 | |||
| PCS | |||||||
| CTL | 50.8 (10.9) | 51.1 (9.9) | 51.0 (10.1) | 0.2 (−1.05, 1.45) | 0.76 | 0.14 (−1.12, 1.41) | 0.83 |
| ISM | 49.9 (12.8) | 50.6 (10.8) | 51.3 (10.6) | ||||
| ISM+ | 50.6 (10.8) | 50.7 (9.0) | 51.1 (9.6) | ||||
| ISM vs. CTL | 0.33 (−1.71, 2.36) | 0.75 | 0.17 (−1.98, 2.32) | 0.88 | |||
| ISM+ vs. CTL | −0.16 (−2.15, 1.82) | 0.87 | −0.57 (−2.63, 1.49) | 0.59 | |||
| MCS | |||||||
| CTL | 37.7 (12.1) | 41.3 (12.6) | 40.8 (12.4) | 3.36 (1.60, 5.13) | 0.0002 | 3.33 (1.54, 5.12) | 0.0003 |
| ISM | 38.8 (13.2) | 45.6 (10.9)b | 45.7 (11.4)b | ||||
| ISM+ | 39.1 (12.3) | 47.4 (11.2)b | 48.7 (11.2)b | ||||
| ISM vs. CTL | 3.56 (0.68, 6.43) | 0.016 | 4.00 (0.96, 7.03) | 0.010 | |||
| ISM+ vs. CTL | 4.53 (1.72, 7.34) | 0.002 | 5.14 (2.24, 8.05) | 0.0006 | |||
Available data used; there were no statistically significant differences between the ISM and ISM+ groups. Sample size, n = all participants (CTL, ISM, and ISM+); descriptive baseline, n = 551 (184, 183, and 184); descriptive week 8, n = 279 (124, 75, and 80); descriptive week 12, n = 251 (120, 61, and 70); linear mixed model, n = 313 (136, 83, and 94). Score ranges, PSS (0–40); MAAS (1–6); ASTI (10–40); PWB-SA (14–84); SVS (7–49); SF-36 (0–100). Higher scores are best with the exception of the PSS
CTL control, ISM Internet-based stress management, ISM+ Internet-based stress management + online message board, PSS Perceived Stress Scale, MAAS Mindfulness Attention Awareness Scale, ASTI Adult Self-transcendence Inventory, PWB-SA Psychological Well-being–Self-acceptance, SVS Subjective Vitality Scale, SF-36 Short Form 36, PCS Physical Component Score, MCS Mental Component Score
aLinear mixed-effects model controls for baseline age, gender, race, education, and income
bSignificantly different from control (CTL) using a p value of <0.05