Table 1.
Corrections as to risk of bias assessment.
| Issue | Relevant studies | Risk | Review's assessment [21] | Corrected evaluation according to Cochrane Handbook∗ | |
|---|---|---|---|---|---|
| A | Erroneous assessment of risk of bias of “random sequence generation (RSQ) | [36–41] | Random sequence generation | High risk | Low risk |
|
| |||||
| B | Erroneous assessment of risk of bias of “allocation concealment” in six studies | [36–41] | Premature knowledge of allocation | High risk | Low risk |
|
| |||||
| C | Erroneous assessment of risk of bias of “incomplete outcome data” | [42–46] | Incomplete outcome data | High risk | High risk of bias is not justified |
|
| |||||
| D1 | Inconsistent evaluation of risk of bias between studies with the same risk | [47] vs. [48] | Allocation concealment | Low risk, for a study with no advantage of mistletoe [47] vs. high risk, for a study with advantage of mistletoe [48] | Equal assessment of risks |
|
| |||||
| D2 | Inconsistent evaluation of risk of bias between studies with the same risk | [47] vs. [44] | Incomplete outcome data | Low risk, for a study with no advantage of mistletoe [47] vs. high risk, for a study with advantage of mistletoe [44] | Equal assessment of risks |
|
| |||||
| E1 | Erroneous assessment of risk of bias of “other sources of bias” | [47] | Other source of bias | Low risk, for a study with no advantage of mistletoe | High risk, as essential criticism has been published [49] towards the Kleeberg publication |
|
| |||||
| E2 | Erroneous assessment of risk of bias of “other sources of bias” | [45, 50, 51] | Other source of bias | High risk | Low risk, a in two of the studies [45, 50] significant results were evaluated |
|
| |||||
| E3 | Erroneous assessment of risk of bias of “other sources of bias” | “at least 16 studies” | Other source of bias | Unclear risk | Low risk, as “bad reporting quality” is not a defined criterion for assessing the risk of bias according to the Cochrane Handbook∗ |
|
| |||||
| E4 | Erroneous assessment of risk of bias of “other sources of bias” | Other source of bias | High risk | Low risk, as a “multiple testing problem” is not attributable to this study as the only primary endpoint “overall survival” has been proven in a confirmatory test | |
|
| |||||
| E5 | Erroneous assessment of risk of bias of “other sources of bias” | [52] | Other source of bias | High risk | Low risk, as the individual best supportive care was described in this study |
∗Cochrane Handbook for Systematic Review of Interventions [26].