Figure 5From: Second hand smoke exposure and the risk of invasive meningococcal disease in children: systematic review and meta-analysis Maternal and paternal smoking and the risk of invasive meningococcal disease. Squares indicate the odds ratio and bars represent 95% confidence intervals (CI). Odds ratios more than one indicate maternal and paternal smoke exposure increases the risk of invasive meningococcal disease in children.Back to article page