Castera et al, 200115 | 0/100 (0) | Random numbers. Allocation concealment not stated | Nurse and patient |
Forbes and Collins 200022 | 0/102 (0) | States randomised. Allocation concealment not stated | None |
Triner et al, 199919 | 0/22 (0) | Computer-generated sequence, sealed envelopes | Investigators and patient |
Burton et al, 199817 | 0/30 (0) | Computer sequence generated by nurse not involved in study | Investigators and patient |
Notini-Gudmarsson et al, 199610 | 2/40 (5) | Randomly assigned. Allocation concealment not stated | Not stated |
Saunders et al, 199516 | 0/131 (0) | Randomly allocated. Allocation concealment not stated | Investigators and patient |
Evans et al, 19951 | 0/30 (0) | Sealed unmarked envelopes from box | Not stated |
Saunders et al, 199420 | 0/89 (0) | Stratified block randomisation | Investigators and patient |
Lindblom et al, 199421 | 0/50 (0) | Block randomisation, blocks of 10. Closed envelopes | Investigators and patient |
Henderson et al, 199014 | Not stated | Not stated | Outcome assessor |
Harrison et al, 198723 | 0/70 (0) | Patient’s choice of analgesia | Unclear |
Kerr et al, 197518 | 35/116 (30) | Block randomisation. Sequentially numbered cylinders | Investigator and patient |