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.
Murray et al. BMC Public Health 2012 12:1062 doi:10.1186/1471-2458-12-1062