Table 7.
Results and interpretation of trial sequential analysis, including diversity adjusted relative information size (DARIS), to detect 25% relative risk reduction in postoperative pulmonary complications, with α=5% and power=80%
| Category of intervention | Information size in meta-analysis | Trial sequential monitoring boundary crossed | DARIS | Result |
|---|---|---|---|---|
| Incentive spirometry | 1940 | No | 3055 | Inconclusive |
| Prophylactic supervised respiratory physiotherapy | 1345 | Yes | 6155 | Firm evidence |
| Prophylactic mucolytic | 452 | No | 1888 | Inconclusive |
| FiO2 0.3 v 0.8 | 1416 | No | 5346 | Inconclusive |
| Lung protective ventilation | 1609 | No | 6184 | Inconclusive |
| CPAP/BIPAP | 437 | No | 7577 | Inconclusive |
| Epidural | 2494 | Yes | 3058 | Firm evidence |
| Smoking cessation | 571 | No | 20748 | Inconclusive |
| Enhanced recovery after surgery pathways | 459 | Yes | 1653 | Firm evidence |
| Goal directed haemodynamic therapy | 3945 | Yes | 2911 | Firm evidence |
| Restrictive v liberal fluids | 795 | No | 9802 | Inconclusive |
BIPAP=bi-level positive airway pressure; CPAP=continuous positive airway pressure; FiO2=fractional inspiration oxygen.
Inconclusive results indicate that further trials are likely to influence conventional meta-analysis results or that risk of random error resulting in false positive result exists.