TABLE 2.
Characteristics of meta-analyses included in umbrella review.
| Author year | Studies, n | Participants, n (I/P/C) | Gestational age (wk) | Ginger intervention dose1 | Comparator (s)2 (dose) |
Duration | AMSTAR-2 analysis | Funding or CoI |
|---|---|---|---|---|---|---|---|---|
| Tan et al. [20], 2023 | 14 (RCT) | 1436 (655/354/427) | <20 | 500–2500 mg/d | Placebo, vitamin B6 (40–160 mg/d), dimenhydrinate (100 mg/d), metoclopramide (30 mg/d) | ≥4 d (4–21 d) | Critically low | None |
| Gaur et al. [26], 2022 | 7 (RCT) | 763 (379/NA/384) | <20 | Ginger (1000–1950 mg/d) | Placebo and vitamin B6 (30–160 mg/d) | ≥3 d (3–21 d) | Low | None |
| Hu et al. [27], 2020 | 13 (RCT) | 1191 (551/223/417) | <20 | Ginger (750–2500 mg/d) | Placebo and vitamin B6 (30–160 mg/d) | ≥3 d (3–21 d) | Critically low | NFSC grant no. 81602852 |
| Sridharan et al. [28], 2018 | 19 (RCT) | 1854 (845/325/684) | <20 | Ginger (450–2500 mg/d) | Placebo, vitamin B6 (30–160 mg/d), dimenhydrinate (100 mg/d), metoclopramide (30 mg/d), chamomile 500 mg/d, pyridoxine and doxylamine (20–30 mg/d) | ≥3 d (3–60 d) | Low | None |
| Matthews et al. [29], 2015 | 16 (RCT) | 1641 (753/310/578) | <20 | Ginger (450–2500 mg/d) | Placebo, vitamin B6 (30–75 mg/d), dimenhydrinate (100 mg/d), metoclopramide (30 mg/d), chamomile (500 mg/d), pyridoxine, and doxylamine (20–30 mg/d) | ≥3 d (3–21 d) | Low | University of Liverpool; Health Research Board, Ireland; Chochrane Fellowship, National Institute for Health Research, UK |
| Viljoen et al. [30], 2014 | 12 (RCT) | 1178 (574/221/383) | <18 | Ginger (500–2500 mg/d) | Placebo, vitamin B6 (30–75 mg/d), metoclopramide (30 mg/d), and dimenhydrinate (100 mg/d) | ≥4 d (4–21 d) | Critically low | None |
| Thomson et al. [31], 2014 | 6 (RCT) | 508 (256/252/NA) | <20 | Ginger (1000–2500 mg/d) | Placebo and vitamin B6 (75 mg/d) | ≥4 d (4–21 d) | Critically low | None |
Abbreviations: AMSTAR-2, A MeaSurement Tool to Assess systematic Reviews; CoI, conflicts of interest; C, comparator (not including placebo); I, intervention; NA, not applicable; P, placebo.
1
Ginger root (rhizome) interventions included preparations of powdered ginger, ginger extracts, or brewed ginger.
2
Comparators were either placebo, vitamin B6, dimenhydrinate, metoclopramide, pyridoxine and doxylamine, or chamomile.