Comparison 2. Quinine versus vitamin E.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Difference in number of cramps in 2 weeks ‐ random‐effects (minus Connolly 1992)	3		No. cramps (Random, 95% CI)	‐0.24 [‐1.29, 0.81]
2 Difference in cramp intensity ‐ fixed‐effect	3		Cramp intensity (Fixed, 95% CI)	‐0.06 [‐0.17, 0.04]
3 Difference in number of cramp days over 2 weeks ‐ random‐effects (minus Connolly 1992)	2		Cramp days (Random, 95% CI)	‐0.28 [‐0.98, 0.43]
4 Participants suffering minor adverse events ‐ random‐effects	2	688	Risk Difference (M‐H, Random, 95% CI)	0.02 [‐0.04, 0.09]
5 Participants suffering major adverse events ‐ random‐effects	3	748	Risk Difference (M‐H, Random, 95% CI)	0.01 [‐0.01, 0.02]