Summary of findings 4. Oral calcium compared with oral vitamin C for leg cramps in pregnancy.
| Oral calcium compared with oral vitamin C for leg cramps in pregnancy | ||||||
| Patient or population: leg cramps in pregnancy Settings: outpatient clinic in Sweden Intervention: oral calcium Comparison: oral vitamin C | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of participants (studies) | Certainty of the evidence (GRADE) | Comments | |
| Assumed risk with oral vitamin C | Corresponding risk with oral calcium | |||||
| Frequency of leg cramps after treatment: never | Study population | RR 1.33 (0.53 to 3.38) | 60 (1 RCT) | ⊕⊝⊝⊝ VERY LOW 1,2 | ||
| 200 per 1000 | 266 per 1000 (106 to 676) | |||||
| *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 certainty: further research is very unlikely to change our confidence in the estimate of effect. Moderate certainty: further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low certainty: 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 certainty: we are very uncertain about the estimate. | ||||||
1Design limitations (‐1).
2Wide CI crossing the line of no effect, few events and small sample size (‐2).