Impact of zinc supplementation on acute lower respiratory infections, pneumonia, and admissions to hospital for all causes in children aged 6-35 months during four months of follow up Zinc Placebo Absolute risk reduction (95% CI) Odds ratio* (95% CI) Child based analysis No of children 1241 1241 No (%) with 1 episodes of acute lower   respiratory tract infections 425 (34.2) 423 (34.1) 0.2% (3.9% to 3.6%) No (%) with 1 episodes of pneumonia 81 (6.5) 112 (9.0) 2.5% (0.4% to 4.6%) No (%) admitted to hospital for any cause 21 (1.8) 30 (2.4)  0.6% (0.5% to 1.8%) Person time based analysis No of four month child periods 1100 1120 Acute lower respiratory tract infections:   Total episodes 581 594   Episodes per four month period 0.53 0.54  1% (2.9% to 5%) 0.98 (0.86 to 1.13) Pneumonia:   Total episodes 88 118   Episodes per four month period 0.08 0.105 2.4% (0.2% to 4.6%) 0.74 (0.56 to 0.99) * After correction for correlation of data by generalised estimating equations. Person time for each child was calculated as total follow up days when reliable informant was available.