Table 1.
Quality assessment of the included studies
| Liu [22] | Page [24] | Page [25] | Page [23] | |
| Selection of prognostic homogenous study population (disease progression) | 1 | 3 | 3 | 3 |
| Concealment of random allocation | 1 | 3 | 3 | 3 |
| Prestratification of prognostically relevant variables | 3 | 3 | 3 | 3 |
| Random allocation (description of procedure) | 2 | 1 | 1 | 3 |
| Registration of loss to follow-up | 1 | 3 | 4 | 4 |
| Blinding of patients | 4 | 4 | 4 | 4 |
| Blinding of persons who implement interventions | 4 | 4 | 4 | 4 |
| Registration of co-interventions that bear on outcome for each group | 3 | 3 | 1 | 3 |
| Blinding of persons who assess treatment effects | 3 | 1 | 1 | 3 |
| Check to what extent blinding was successful | 3 | 3 | 3 | 3 |
1 = Item is properly addressed, 2 = Item is partially addressed, 3 = Item is not properly addressed or not stated, 4 = Item is not applicable