Demographic and clinical characteristics of both study groups at baseline
| Characteristic | Randomized sample n = 60 | CCA* sample n = 47 | Modified ITT† sample n = 43 | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Probiotic n = 30 | Placebo n = 30 | Group comparison | Probiotic n = 21 | Placebo n = 26 | Group comparison | Probiotic n = 19 | Placebo n = 24 | Group comparison | |
| Sex, female, n (%) | 20 (66.7) | 16 (53.33) | χ21 = 0.63, p = 0.43 | 14 (67) | 13 (50) | χ21 = 0.73, p = 0.49 | 14 (74) | 12 (50) | χ21 = 1.60, p = 0.21 |
| Age, mean ± SD | 38.03 ± 11.32 | 37.87 ± 10.32 | W = 443, p = 0.92 | 39.43 ± 11.45 | 38.77 ± 10.32 | W = 278, p = 0.92 | 39.21 ± 11.53 | 38.04 ± 10.24 | W = 238.5, p = 0.81 |
| BMI, mean ± SD | 23.53 ± 3.82 | 25.20 ± 3.50 | W = 334, p = 0.13 | 23.50 ± 3.67 | 24.88 ± 3.95 | W = 207, p = 0.23 | 23.83 ± 3.66 | 25.13 ± 4.01 | W = 177, p = 0.30 |
| Smoking, n (%) | |||||||||
| ≥ 1/day | 9 (30) | 12 (40) | χ24 = 3.21, p = 0.52 | 7 (33) | 11 (42) | χ21 = 0.27, p = 0.60 | 5 (26) | 10 (42) | χ21 = 0.87, p = 0.35 |
| NA | 10 (33.3) | 8 (26.7) | 3 (14) | 5 (19) | 3 (16) | 5 (21) | |||
| Hospitalization, n (%) | |||||||||
| 1 | 10 (33) | 13 (43) | W = 274, p = 0.41 | 8 (38) | 12 (46) | W = 224.5, p = 0.45 | 7 (37) | 12 (50) | W = 210.5, p = 0.32 |
| 2 | 4 (13) | 5 (17) | 4 (19) | 5 (19) | 4 (21) | 4 (17) | |||
| 3 | 3 (10) | 3 (10) | 3 (14) | 3 (12) | 3 (16) | 3 (13) | |||
| 4 | 0 (0) | 1 (3) | 0 (0) | 1 (4) | 0 (0) | 1 (4) | |||
| 5 | 3 (10) | 0 (0) | 3 (14) | 0 (0) | 3 (16) | 0 (0) | |||
| ≥ 6 | 1 (3) | 1 (3) | 0 (0) | 1 (4) | 0 (0) | 1 (4) | |||
| NA | 9 (30) | 7 (23) | 3 (14) | 4 (15) | 2 (11) | 3 (13) | |||
| Education, n (%) | |||||||||
| Primary | 9 (30) | 6 (20) | W = 423, p = 0.42 | 7 (33) | 4 (15) | W = 269.5, p = 0.88 | 6 (32) | 4 (17) | W = 237, p = 0.63 |
| Secondary | 3 (10) | 12 (40) | 3 (14) | 12 (46) | 3 (16) | 12 (50) | |||
| Tertiary | 16 (53) | 9 (30) | 11 (52) | 9 (35) | 10 (53) | 7 (29) | |||
| NA | 2 (7) | 3 (10) | 0 (0) | 1 (4) | 0 (0) | 0 (0) | |||
| Medication, DDD, mean ± SD | |||||||||
| Antidepressant equivalents | NA | NA | NA | 1.73 ± 1.30 | 1.79 ± 1.09 | W = 253, p = 0.68 | 1.86 ± 1.30 | 1.82 ± 1.12 | W = 227, p = 0.99 |
| Antipsychotics equivalents | NA | NA | NA | 0.30 ± 0.68 | 0.22 ± 0.30 | W = 278, p = 0.92 | 0.33 ± 0.71 | 0.24 ± 0.31 | W = 241, p = 0.76 |
| Clinical measures, mean ± SD | |||||||||
| HAM-D | 18.90 ± 4.7 | 16.7 ± 4.10 | W = 552, p = 0.08 | 18.93 ± 4.78 | 16.5 ± 4.04 | W = 363, p = 0.05 | 19.13 ± 4.89 | 16.5 ± 4.18 | W = 311, p = 0.04 |
| BDI | 22.5 ± 8.10 | 22.12 ± 9.90 | W = 461.5, p = 0.69 | 22.38 ± 7.54 | 22.33 ± 10.17 | W = 257.5, p = 0.96 | 21.53 ± 7.59 | 22.31 ± 9.94 | W = 218.5, p = 0.96 |
| STAI1 | 42.32 ± 5.525 | 41.10 ± 6.53 | W = 472.5, p = 0.42 | 49.75 ± 13.89 | 52.36 ± 10.40 | W = 229.5, p = 0.65 | 49 ± 14.11 | 51.83 ± 10.61 | W = 191, p = 0.68 |
| GSRS‡ | 30.21 ± 9.94 | 29.53 ± 12.06 | W = 479, p = 0.51 | 28.52 ± 9.48 | 29.83 ± 12.45 | W = 261, p = 0.98 | 28.16 ± 9.65 | 29.96 ± 12.79 | W = 211.5, p = 0.87 |
| Compliance, %, mean ± SD | NA | NA | NA | 83 ± 17.21 | 86 ± 11.72 | W = 231, p = 0.76 | 87 ± 8.44 | 88 ± 8.17 | W = 186, p = 0.84 |
BDI = Beck Depression Inventory; BMI = body mass index; CCA = complete case analysis; DDD = defined daily dose; GSRS = Gastrointestinal Symptom Rating Scale; HAM-D = Hamilton Rating Scale for Depression; ITT = intention to treat; NA = not applicable; SD = standard deviation; STAI1 = State–Trait Anxiety Inventory 1.
↵* Referred to as ITT in Schaub et al.19
↵† Also referred to as modified ITT in Schaub et al.19
↵‡ Non-normally distributed, b square root–transformed.