Sensitivity analysis with respect to the quality of study
| Quality of study | ES of pain reduction and 95% CI | |
|---|---|---|
| Paracetamol v placebo | NSAIDs v paracetamol | |
| *p⩽0.05; **p⩽0.01. | ||
| Study design | ||
| Double blind parallel | 0.09 (−0.43 to 0.61) | 0.20 (0.08 to 0.33)* |
| Double blind crossover | 0.23 (0.02 to 0.44)* | 0.19 (0.03 to 0.36)* |
| Others | − | 0.22 (−0.34 to 0.78) |
| Withdrawal rate | ||
| <10% | − | 0.17 (0.05 to 0.31)* |
| ⩾10% | 0.21 (0.02 to 0.41)* | 0.22 (0.09 to 0.36)** |