Table 2 Methodological quality of meta-analyses.
Questions | Supported by industry | Non-profit support or no support | P value* | Undeclared support |
|---|---|---|---|---|
(N = 10) | (N = 18) | (N = 11) | ||
1. Were the search methods used to find evidence on the primary question stated? | 6 | 18 | 0.02 | 6 |
2. Was the search for evidence reasonably comprehensive? | 4 | 17 | <0.01 | 6 |
3. Were the criteria used for deciding which studies to include reported? | 5 | 17 | 0.03 | 10 |
4. Was bias in the selection of studies avoided? | 1 | 12 | 0.01 | 3 |
5. Were the criteria used for assessing the validity of the included studies reported? | 3 | 15 | 0.02 | 5 |
6. Was the validity of all studies referred to in the text assessed using appropriate criteria? | 1 | 10 | 0.04 | 1 |
7. Were the methods used to combine the findings of the relevant studies reported? | 9 | 17 | 1.00 | 10 |
8. Were the findings of the relevant studies combined appropriately? | 7 | 16 | 0.46 | 8 |
9. Were the conclusions made by the author(s) supported by the data reported? | 9 | 15 | 1.00 | 9 |
Overall quality (1–7) (median score) | 2.5 | 6 | <0.01 | 3 |