A number of recent reviews have systematically collated and pooled the results of published studies in an attempt to estimate the magnitude of the risks associated with environmental tobacco exposure. Some results of these meta-analyses are summarised here. This shows the risk of certain respiratory illnesses in children exposed to one or more parents who smoke, relative to children of non-smoking parents. A relative risk of 1.0 represents no difference between the two groups.

Cook DG, Strachan DP. Health effects of passive smoking in children: summary of the evidence and recommendations for further resesarch. Thorax 1999;54:357-366