eTable 4. Results of the subgroup analysis (IG: 112 rehabilitants versus CG: 205 non-rehabilitants).
| Outcome | Group | N | T0 | T1 | Δ T0−T1 | Difference ΔIG vs. ΔCG | |
| M (SD) | M (SD) | p value*1 | ES*2 [95% CI] | ||||
| Primary outcome | |||||||
| Limitation in social participation (IMET) (0–90) (higher scores = worse) | IG | 112 | 35.37 (19.25) | 25.43 (20.13) | 9.94 (22.60) | 0.005 | 0.36 [0.13; 0.60] |
| CG | 203 | 32.44 (17.91) | 29.46 (19.97) | 2.98 (17.02) | |||
| Secondary outcomes | |||||||
| Disease activity (GIBDI*3) (0–18) (higher scores = worse) | IG | 101 | 5.54 (2.70) | 3.50 (2.69) | 2.04 (3.34) | <0.001 | 0.59 [0.34; 0.84] |
| CG | 173 | 5.15 (2.79) | 4.97 (3.20) | 0.17 (3.06) | |||
| Self-monitoring and insight (heiQ scale) (1–4) (higher scores = better) |
IG | 112 | 2.96 (0.39) | 3.25 (0.35) | 0.29 (0.40) | <0.001 | 0.44 [0.20; 0.67] |
| CG | 196 | 2.99 (0.47) | 3.11 (0.45) | 0.12 (0.38) | |||
| Constructive attitudes (heiQ scale) (1–4) (higher scores = better) |
IG | 112 | 3.12 (0.53) | 3.34 (0.48) | 0.22 (0.48) | 0.005 | 0.34 [0.10; 0.57] |
| CG | 197 | 3.14 (0.54) | 3.21 (0.57) | 0.06 (0.47) | |||
| Emotional well-being (heiQ scale) (1–4) (higher scores = worse) |
IG | 109 | 2.38 (0.67) | 1.99 (0.61) | −0.39 (0.64) | <0.001 | 0.47 [0.24; 0.71] |
| CG | 200 | 2.36 (0.65) | 2.26 (0.64) | −0.10 (0.60) | |||
| Psychological distress (PHQ-4) (0–12) (higher scores = worse) |
IG | 112 | 4.48 (2.79) | 2.82 (2.30) | 1.66 (2.77) | <0.001 | 0.47 [0.23; 0.70] |
| CG | 201 | 4.21 (2.72) | 3.78 (2.68) | 0.43 (2.55) | |||
| Vitality (SF-36) (0–100) (higher scores = better) |
IG | 112 | 35.05 (15.92) | 49.64 (19.45) | −14.60 (20.69) | <0.001 | 0.63 [0.40; 0.87] |
| CG | 204 | 36.74 (17.74) | 39.49 (20.53) | −2.75 (17.56) | |||
| Level of being informed about IBD (NRS 0–10) |
IG | 112 | 6.48 (2.31) | 7.81 (1.95) | −1.33 (2.55) | 0.002 | 0.41 [0.17; 0.64] |
| CG | 204 | 6.73 (2.37) | 7.17 (2.47) | −0.44 (1.98) | |||
| Health-related quality of life (EQ-VAS) (0–100) (higher scores = better) |
IG | 111 | 59.98 (16.65) | 71.40 (16.61) | −11.41 (19.46) | <0.001 | 0.56 [0.32; 0.79] |
| CG | 204 | 63.46 (15.76) | 65.03 (18.24) | −1.57 (16.73) | |||
| Current state of health a lot/somewhat at T1 (compared to T0) better |
IG | 112 | 82 (73.2%) | <0.001 | OR = 5.6 [3.4; 9.4] |
||
| CG | 205 | 67 (32.7%) | |||||
| Employment status at T1 Working, yes | IG | 112 | 101 (90.2%) | 0.345 | OR = 0.7 [0.3; 1.5] |
||
| CG | 205 | 191 (93.2%) | |||||
| Negative subjective employment prognosis (SPE) at T1 Score ≥ 2 |
IG | 107 | 41 (38.3%) | 0.080 | OR = 0.7 [0.4; 1.1] |
||
| CG | 201 | 98 (48.8%) | |||||
| Number of sick days taken off from work*4 in the past 3 months (0–90) |
IG | 99 | 12.32 (18.52) | 9.34 (20.44) | 2.98 (26.26) | 0.201 | 0.16 [−0.09; 0.41] |
| CG | 182 | 9.14 (14.28) | 9.75 (19.18) | −0.62 (20.14) | |||
*1 Non-adjusted; for secondary outcomes, only p values ≤ 0.004 are statistically significant after Bonferroni adjustment.
*2 Cohen’s d with denominator as mean pooled SD and corrected for different group sizes; positive d value = advantage IG, negative value = advantage CG
*3 GIBDI incalculable for stoma and indeterminate colitis.
*4 Excluded are those at T1 who are not working.
IBD, inflammatory bowel disease; EQ-VAS, EuroQuol Visual Analogue Scale; ES, effect size; GIBDI, German Inflammatory Bowel Disease Activity Index; heiQ, Health Education Impact Questionnaire; CG, control group; CI, confidence interval; IG, intervention group; IMET, index for measuring limitations of participation (“Index zur Messung von Einschränkungen der Teilhabe”); M, mean; N, number of valid values; NRS, numerical rating scale; OR, odds ratio under control of baseline distribution; PHQ-4, Patient Health Questionnaire (short form with 4 items); SD, standard deviation; SF-36, Short Form 36 questionnaire; SPE, subjective prognostic employment scale (without pensioners); T0, baseline; T1, follow-up