Zinc supplementation as an adjunct to standard therapy in childhood nephrotic syndrome - a systematic review

Table 2 Zinc for nephrotic syndrome (steroid sensitive nephrotic syndrome)

	Patient or population: Patients with nephrotic syndrome
	Settings: Hospital setting
	Intervention: Zinc
Outcomes	Illustrative comparative risks3 (95%CI)		Relative effect (95%CI)	No. of participants (studies)	Quality of the evidence (GRADE)
	Assumed risk	Corresponding risk
	Control	Zinc
Frequency of relapses in 12 mo Follow-up: 12 mo	The mean frequency of relapses in 12 mo in the control groups was 2%	The mean frequency of relapses in 12 mo in the intervention groups was 0.2 lower (0.71 lower to 0.31 higher)		81 (1 study)	Very low1,2
Frequency of relapses in 6 mo Follow-up: 12 mo	The mean frequency of relapses in 6 mo in the control groups was 19%	The mean frequency of relapses in 6 mo in the intervention groups was 0.19 lower (0.57 lower to 0.19 higher)		81 (2 studies)	Very low1,2
Risk of relapse per year Follow-up: 12 mo	725 per 1000	500 per 1000 (326 to 776)	RR = 0.69 (0.45 to 1.07)	78 (1 study)	Very low1,2
Mean length of time to next relapse Follow-up: 12 mo	The mean length of time to next relapse in the control groups was 1.5 mo	The mean length of time to next relapse in the intervention groups was 1.5 higher (0 to 0 higher)		78 (1 study)	Very low1,2

¹Single trial;

²Small sample size;

³The basis for the assumed risk (e.g., the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95%CI) 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.