Table 2.
Symptom severity, quality of life, and functioning over time by treatment group in the intent-to-treat sample (n = 80)
| Outcome measure | App-based CBT (n = 40) |
Waitlist (n = 40) |
Est. mean group difference M [95% CI] | p | Effect size (group difference) d [95% CI] | ||
|---|---|---|---|---|---|---|---|
| M (SD) | n | M (SD) | n | ||||
|
| |||||||
| BDD-YBOCS | |||||||
| Baseline | 29.9 (4.0) | 40 | 30.9 (4.8) | 40 | – | – | – |
| Week 6 | 23.8 (6.9) | 35 | 27.1 (6.0) | 38 | – | – | – |
| Week 12 | 16.8 (7.5) | 31 | 26.7 (6.2) | 37 | −10.1 [−13.3, −7.0] | <0.001 | −1.44 [−1.99, −0.91] |
| Within-group effect size | −2.26 [−2.93, −1.58] | −0.75 [−1.03, −0.47] | |||||
| BABS | |||||||
| Baseline | 15.1 (3.2) | 40 | 14.5 (3.4) | 40 | – | – | – |
| Week 6 | 12.3 (5.2) | 35 | 13.5 (4.8) | 38 | – | – | – |
| Week 12 | 8.3 (5.0) | 30 | 13.2 (4.9) | 37 | −4.8 [−7.1, −2.6] | <0.001 | −1.00 [−1.51, −0.48] |
| Within-group effect size | −1.67 [−2.18, −1.15] | −0.29 [−0.53, −0.06] | |||||
| QIDS-SR | |||||||
| Baseline | 11.1 (4.4) | 40 | 11.4 (4.0) | 40 | – | – | – |
| Week 6 | 10.1 (4.8) | 34 | 10.1 (4.7) | 36 | – | – | – |
| Week 12 | 7.1 (4.5) | 28 | 10.3 (4.2) | 36 | −3.3 [−5.3, −1.2] | 0.002 | −0.74 [−1.26, −0.23] |
| Within-group effect size | −0.91 [−1.39, −0.42] | −0.28 [−0.66, 0.11] | |||||
| SDS | |||||||
| Baseline | 16.0 (6.6) | 40 | 17.1 (6.8) | 40 | – | – | – |
| Week 6 | 11.1 (6.4) | 34 | 13.2 (7.2) | 37 | – | – | – |
| Week 12 | 7.6 (6.8) | 28 | 13.5 (7.3) | 37 | −5.9 [−9.2, −2.5] | <0.001 | −0.82 [−1.34, −0.31] |
| Within-group effect size | −1.25 [−1.78, −0.72] | −0.51 [−0.81, −0.21] | |||||
| Q-LES-Q-SF | |||||||
| Baseline | 52.7 (16.3) | 40 | 48.3 (10.2) | 40 | – | – | – |
| Week 6 | 54.0 (16.4) | 34 | 52.1 (12.2) | 37 | – | – | – |
| Week 12 | 66.5 (16.4) | 28 | 55.2 (12.4) | 37 | 11.8 [4.9, 18.6] | 0.001 | 0.79 [0.28, 1.30] |
| Within-group effect size | 0.84 [0.41, 1.27] | 0.66 [0.28, 0.93] | |||||
BDD-YBOCS, Yale-Brown Obsessive Compulsive Scale Modified for BDD; BABS, Brown Assessment of Beliefs Scale; QIDS-SR, Quick Inventory of Depressive Symptomatology – Self Report; SDS, Sheehan Disability Scale; Q-LES-Q-SF, Quality of Life, Enjoyment, and Satisfaction Questionnaire – Short Form. Within-group effect sizes were calculated as differences from pre- to post-treatment (baseline to week 12) divided by the standard deviations of raw scores and using raw means for completers only. Effect sizes for between-group differences at week 12 are Cohen’s d based on raw means. Estimated mean group differences and p values are model-based estimates from intent-to-treat analyses.