. 2011 Apr 13;11(Suppl 3):S23. doi: 10.1186/1471-2458-11-S3-S23

Table 1.

Quality assessment of overall evidence for effect of zinc supplementation (alone) in reducing morbidity and mortality in children > 5 years of age in developing countries

No of studies (ref)	Study Design	Limitations	Consistency	Generalizability to Population of Interest	Generalizability to intervention of interest	Relative Risk (95% CI)
*Outcome: All-cause mortality: Quality of evidence: Low*

7	RCTs	Sequence generation and allocation concealment was unclear in few of the included studies	I²= 50%	Yes (all studies were conducted in developing countries)	The median dose of supplementation was 10 mg/day and median duration of supplementation was for 6 months.	0.91 (0.82-1.01)

*Outcome: Diarrhea specific mortality: Quality of evidence: Low*

4	RCTs	Allocation concealment was unclear in two of the included studies	I²=0%	Yes (all studies were conducted in developing countries)	The median dose of supplementation was 10 mg/day and median duration of supplementation was for 6 months.	0.82 (0.64-1.05)

*Outcome: Diarrhea specific morbidity: Quality of evidence: Moderate*

14	RCTs	Sequence generation and allocation concealment was unclear in few of the included studies	I²=79%	Yes (all studies were conducted in developing countries)	The median dose of supplementation was 10 mg/day and median duration of supplementation was for 6 months.	0.87 (0.81-0.94)

*Outcome: Pneumonia specific mortality: Quality of evidence: Low*

4	RCTs	Allocation concealment was unclear in two of the included studies	I²= 39%	Yes (all studies were conducted in developing countries)	The median dose of supplementation was 10 mg/day and median duration of supplementation was for 6 months.	0.85 (0.65-1.11)

*Outcome: Pneumonia specific morbidity: Quality of evidence: Moderate*

6	RCTs	Sequence generation and allocation concealment was unclear in few of the included studies	I²=0%	Yes (all studies were conducted in developing countries)	The median dose of supplementation was 10 mg/day and median duration of supplementation was for 6 months.	0.81 (0.73-0.90)

*Outcome: Malaria specific mortality: Quality of evidence: Low*

1	RCT	None	NA	Study conducted in Zanzibar	Dose of supplementation was 10 mg/dl for children > 1 year and 5mg/day for children < 1 years.	0.90 (0.77-1.06)

*Outcome: Malaria specific morbidity: Quality of evidence: Low*

4	RCTs	Allocation concealment was unclear in two of the included studies	I²=0%	Yes (all studies were conducted in developing countries)	The median dose of supplementation was 10 mg/day and median duration of supplementation was for 6 months.	0.92 (0.82-1.04)