Table 3.
Summary of risk of bias assessment.
| Selection bias | Study design | Confounders | Blinding | Data collection methoda | Withdrawals and dropouts | Attrition rateb | Global rating | |
|---|---|---|---|---|---|---|---|---|
| Brakenridge et al. 201637; Brakenridge et al. 201638 | W | S | S | W | S | W | IG: 62% CG: 47% Overall: 54% | Weak |
| Finkelstein et al. 201539; Finkelstein et al. 201640 | W | S | S | M | S | S | IG1: 21%, IG2: 24%, IG3: 14% CG: 17% Overall: 19% | Moderate |
| Ganesan et al. 201641 | W | M | S | M | M | W | IG: 47% | Weak |
| Gilson et al. 201655; Gilson et al. 201756 | W | M | W | M | S | W | IG: 57% | Weak |
| Gremaud et al. 201860 | W | S | S | M | S | S | IG: 0% CG: 1% Overall: 1% | Moderate |
| Jones 201642 | W | M | W | M | S | M | IG1: 32%, IG2: 16% CG: 25% Overall: 24% | Weak |
| Koyle 201343 | W | S | S | M | M | S | IG: 17% CG: 11% Overall: 14% | Moderate |
| Losina et al. 201757 | W | M | W | M | M | S | IG: 3% | Weak |
| Neil-Sztramko et al. 201758 | W | M | W | M | S | S | IG: 0% | Weak |
| Olsen et al. 201861 | W | M | W | M | S | M | IG: 39% | Weak |
| Patel et al. 201644 | W | S | S | M | M | S | IG1: 3%, IG2: 8%, IG3: 4% CG: 4% Overall: 5% | Moderate |
| Patel et al. 201645 | W | S | W | M | M | S | IG1: 3%, IG2: 4%, IG3: 3% CG: 6% Overall: 4% | Weak |
| Patel et al. 201862 | W | S | S | M | M | S | IG1: 5%, IG2: 5%, IG3: 7% CG: 8% Overall: 6% | Moderate |
| Poirier et al. 201646 | W | S | S | M | S | S | IG: 20% CG: 17% Overall: 18% | Moderate |
| Reed et al. 201863 | W | S | S | M | M | S | IG1: 8%, IG2: 0%, IG3: 4% Overall: 4% | Moderate |
| Reijonsaari et al. 200947; Reijonsaari et al. 201248 | W | S | S | W | S | M | IG: 35% CG: 32% Overall: 33% | Weak |
| Rowe-Roberts et al. 201449 | W | M | W | M | S | M | IG: 34% | Weak |
| Schrager et al. 201750 | M | M | W | M | W | M | IG: 35% | Weak |
| Simons et al. 201864; Simons et al. 201865 | W | S | S | M | S | S | IG: 12% CG: 19% Overall: 15% | Moderate |
| Skogstad et al. 201651 | W | M | S | M | W | S | IG: 15% | Weak |
| Slootmaker et al. 200952 | W | S | S | M | M | M | IG: 26% CG: 18% Overall: 22% | Moderate |
| Thorndike et al. 201453 | S | M | S | M | S | S | Phase 1 IG: 4% CG: 6% Phase 2 IG: 8% Whole trial: 13% | Strong |
| Torquati et al. 201866 | W | M | W | M | S | W | IG: 74% | Weak |
| van Dantzig et al. 201354 | W | S | S | M | W | S | Attrition not reported but 85/86 participants appear to have completed the trial based on final data (i.e. 1.2% attrition). | Weak |
| Yeung et al. 201759 | W | M | W | M | S | S | IG: 14% | Weak |
S: strong; M: moderate; W: weak; IG: Intervention Group; CG: Control/Comparison Group
aValidity and reliability of primary outcome. For data collection method, studies were rated as ‘strong’ if the measure had known validity and reliability, ‘moderate’ if the measure had reasonable validity or reliability, and ‘weak’ if validity and reliability were unknown.
bPercentage of participants failing to provide data at final follow-up (to nearest whole percentage)