Summary of findings 2.
Acetaminophen plus Diphenhydrammine versus placebo (Unit of randomisation: transfusion) for requirement of prophylaxis to avoid allergic and febrile non‐haemolytic transfusion reactions
| Acetaminophen plus Diphenhydrammine versus placebo (Unit of randomisation: transfusion) for requirement of prophylaxis to avoid allergic and febrile non‐haemolytic transfusion reactions | ||||||
| Patient or population: patients with requirement of prophylaxis to avoid allergic and febrile non‐haemolytic transfusion reactions Settings: Hospital Intervention: Acetaminophen plus Diphenhydrammine versus placebo (Unit of randomisation: transfusion) | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of Participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| Control | Acetaminophen plus Diphenhydrammine versus placebo (Unit of randomisation: transfusion) | |||||
| Fever ‐ Per protocol analysis | Study population | RR 1.77 (0.57 to 5.49) | 98 (1 study) | ⊕⊕⊝⊝ low1,2,3 | ||
| 87 per 1000 | 154 per 1000 (50 to 478) | |||||
| Medium risk population | ||||||
| 87 per 1000 | 154 per 1000 (50 to 478) | |||||
| Anaphylatic reactions ‐ not reported | Study population | RR 0 (0 to 0) | 0 (0) | See comment | ||
| See comment | See comment | |||||
| Medium risk population | ||||||
| Hives ‐ Per protocol analysis | Study population | RR 0.13 (0.01 to 2.39) | 98 (1 study) | ⊕⊕⊝⊝ low1,2 | ||
| 65 per 1000 | 8 per 1000 (1 to 155) | |||||
| Medium risk population | ||||||
| 65 per 1000 | 8 per 1000 (1 to 155) | |||||
| Death ‐ not reported | Study population | RR 0 (0 to 0) | 0 (0) | See comment | ||
| See comment | See comment | |||||
| Medium risk population | ||||||
| Adverse events | Study population | RR 0 (0 to 0) | 0 (0) | See comment | ||
| See comment | See comment | |||||
| Medium risk population | ||||||
| *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; RR: Risk ratio; | ||||||
| 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. | ||||||
1 Data on randomisation (sequence generation, allocation concealment) unavailable. 2 Not applicable (1 trial included) 3 Low event rate (36 reported)