Summary of findings for the main comparison. Proportion of participants experiencing at least 50% of maximum pain relief at 4 hours.
| IV paracetamol/propacetamol compared to placebo or other analgesics for postoperative pain | |||||
| Patient or population: patients with postoperative pain Settings: hospital Intervention: IV paracetamol/propacetamol Comparison: placebo or other analgesics | |||||
| Comparison | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of participants (studies) | Quality of the evidence (GRADE) | |
| Assumed risk | Corresponding risk | ||||
| Placebo or other analgesics | IV paracetamol/propacetamol | ||||
| Para/propacetamol vs placebo see footnote1 | 156 per 1000 | 394 per 1000 (313 to 497) | RR 2.53 (2.01 to 3.19) | 1149 (11 studies) | ⊕⊕⊕⊕ high2,3 |
| Paracetamol vs placebo see footnote1 | 66 per 1000 | 317 per 1000 (152 to 661) | RR 4.8 (2.3 to 10) | 393 (5 studies) | ⊕⊕⊕⊝ moderate2,3,4 |
| Propacetamol vs placebo see footnote1 | 188 per 1000 | 411 per 1000 (327 to 520) | RR 2.19 (1.74 to 2.77) | 756 (8 studies) | ⊕⊕⊕⊝ moderate2,3,4 |
| Para/propacetamol vs NSAIDs see footnote1 | 599 per 1000 | 605 per 1000 (515 to 707) | RR 1.01 (0.86 to 1.18) | 353 (5 studies) | ⊕⊕⊝⊝ low4,5 |
| Paracetamol vs NSAIDs see footnote1 | 631 per 1000 | 568 per 1000 (454 to 713) | RR 0.9 (0.72 to 1.13) | 130 (2 studies) | ⊕⊝⊝⊝ very low4,5,6 |
| Propacetamol vs NSAIDs see footnote1 | 577 per 1000 | 624 per 1000 (496 to 774) | RR 1.08 (0.86 to 1.34) | 223 (3 studies) | ⊕⊝⊝⊝ very low2,4,5,6 |
| Paracetamol vs propacetamol see footnote1 | 428 per 1000 | 419 per 1000 (329 to 530) | RR 0.98 (0.77 to 1.24) | 361 (3 studies) | ⊕⊕⊕⊝ moderate4 |
| *The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval; IV: intravenous; NSAIDs: nonsteroidal anti‐inflammatory drugs; RR: risk ratio; SPID = summed pain intensity difference; TOTPAR = total pain relief; VAS: visual analog scale | |||||
| GRADE Working Group grades of evidence High quality: Further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate. | |||||
1TOTPAR or SPID using either VAS or categorical data, and calculating their corresponding percentage of theoretical maximum TOTPAR and SPID. 2Considerable unexplained heterogeneity exists between studies. 3Large effect. 4Total # events < 300. 5Different NSAIDs studied. 6Wide confidence interval that includes no effect and appreciable benefit and/or harm.