Table 5.
Risk of bias.
| Study | Random sequence generation | Allocation concealment | Blinding of outcome assessment | Incomplete outcome data | Selective reporting | Other bias | Therapist factors bias |
|---|---|---|---|---|---|---|---|
| Burns et al. [56] | Low risk | Low risk | Low risk | Low risk | Low risk | Unclear | Low risk |
| Carter et al. [58] | Unclear | Unclear | Unclear | High risk | Unclear | High risk | Unclear |
| Cho et al. [59] | Unclear | Unclear | Low risk | Low risk | Unclear | Low risk | Low risk |
| Dimidjian et al. [48] | Low risk | Low risk | Low risk | Low risk | Low risk | Unclear | High risk |
| Forsel et al. [60] | Low risk | Low risk | High risk | Low risk | Low risk | Unclear | Unclear |
| Hayden et al. [61] | Low risk | Unclear | Low risk | Unclear | High risk | High risk | Low risk |
| Milgrom et al. [62] | Low risk | Low risk | Low risk | Low risk | Low risk | High risk | Low risk |
| Milgrom et al. [39] | Low risk | Low risk | High risk | Low risk | High risk | High risk | Low risk |
| Milgrom et al. [64] | Low risk | Low risk | Low risk | Low risk | Low risk | High risk | Unclear |
| Ngai et al. [17] | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | High risk |
| O'Mahen et al. [68] | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk |
| O'Mahen et al. [69] | Low risk | Low risk | Low risk | Unclear | Unclear | High risk | Low risk |
| O'Mahen et al. [71] | Low risk | Low risk | Unclear | Low risk | Unclear | High risk | Unclear |
| Pugh et al. [72] | Low risk | Low risk | Low risk | Low risk | Low risk | High risk | Low risk |
| Rondung et al. [73] | Unclear | Unclear | Low risk | Low risk | High risk | High risk | Low risk |
| Shaw et al. [76] | Low risk | Low risk | Low risk | Low risk | Low risk | High risk | Unclear |
| Suchan et al. [78] | Low risk | Low risk | Low risk | Unclear | Low risk | High risk | Low risk |
| Trevillion et al. [79] | Low risk | Low risk | Low risk | Low risk | Low risk | High risk | High risk |
| Wozney et al. [80] | Low risk | Low risk | Low risk | Low risk | Unclear | High risk | High risk |
Note: High risk would be where the therapist has minimal psychological therapy qualifications/training, for example someone with an undergraduate degree in psychology with no further training, or a midwife with perhaps a few days of training in CBT but no previous therapeutic experience. Low risk would be a therapist with at least moderate psychological therapy qualifications/training, for example a clinical psychologist or a CBT therapist or a psychological wellbeing practitioner with CBT training. Please note that social workers in America have roughly equivalent training and experience in psychological therapies as psychological practitioners in the UK.