Table 2. Quality analysis of included studies.
| Reference | Randomization | Blinding | Describing withdrawals | Allocation concealment | Jadad’s scores |
|---|---|---|---|---|---|
| Downing et al. (1981) | randomization tables | double blind | yes | unclear | 5B |
| Edwards (1986) | just mentioned random | double blind | yes | unclear | 4B |
| Finucane (1986) | Unclear | double blind | NA | unclear | 2B |
| Galloway (1986) | just mentioned random | double blind | yes | unclear | 4B |
| Gravenstein et al. (1984) | just mentioned random | double blind | yes | unclear | 4B |
| Pandit (1985) | just mentioned random | double blind | yes | sealed ampoules | 4A |
| Pandit (1986) | just mentioned random | double blind | yes | unclear | 4B |