Summary of results of meta-analyses
| Comparator | Outcome | Studies (n) | Pooled effect estimate including all studies | Studies (n) | Pooled estimates excluding studies with ingredients other than honey* |
| Placebo | Combined symptom score | 2 (372) | SMD −0.63, 95% CI −1.44 to 0.18, I2=91% | 1 (270) | SMD −1.03, 95% CI −1.32 to −0.75 |
| Usual care | Combined symptom score | 3 (333) | MD −3.96, 95% CI −5.42 to −2.51, I2=0% | 2 (192) | MD −4.47, 95% CI −6.47 to −2.48, I2=0% |
| Cough frequency | 8 (832) | SMD −0.36, 95% CI −0.50 to −0.21, I2=0% | 6 (586) | SMD −0.40, 95% CI −0.58 to −0.21, I2=0% | |
| Cough severity | 5 (598) | SMD −0.44, 95% CI -0.64, to -0.25, I2=20% | 4 (457) | SMD −0.44, 95% CI −0.70 to −0.17, I2=40% | |
| Improvement | 2 (334) | OR 1.01, 95% CI 0.45 to 2.27, I2=56% | 1 (200) | OR 0.73, 95% CI 0.42 to 1.27 | |
| Throat pain recovery by day 5 | 1 (200) | OR 0.75, 95% CI 0.43 to 1.32 | No change | ||
| Fever recovery by day 5 | 1 (200) | OR 2.58, 95% CI 1.22 to 5.46 | No change | ||
| Dextromethorphan† | Combined symptom score | 1 (68) | MD −2.32, 95% CI −5.88 to 1.24 | NA | |
| Cough frequency | 2 (137) | MD −0.52, 95% CI −1.51 to 0.46, I2=0% | NA | ||
| Cough severity | 2 (137) | MD −0.56, 95% CI −1.65 to 0.53, I2=0% | NA | ||
| Diphenhydramine† | Combined symptom score | 1 (87) | MD −5.31, 95% CI −7.96 to −2.67 | NA | |
| Cough frequency | 4 (385) | SMD −0.29, 95% CI −0.58 to −0.01, I2=46% | 3 (280) | SMD −0.41, 95% CI −0.69 to −0.14, I2=17% | |
| Cough severity | 3 (280) | SMD −0.50, 95% CI −0.88 to −0.13, I2=53% | NA |
Pooled results compare honey to comparator, meta-analysed with Mantel–Haenszel random effects models. Studies=number of included studies reporting outcome.
*Results excluding Cohen 2017,21 Gupta 2016,22 Miceli Sopo 201518 and Canciani 201419.
†Subgroup of usual care.
MD, mean difference; n, total number of participants; NA, not applicable, as these studies were not in the primary analysis so results are unchanged; SMD, standard mean difference.