Description of graph: Cross-sectional studies

This is a bar chart showing percentage reporting cough by parents’ smoking (neither, one, both) and within that child’s smoking (never, occasional, once per week or more).

Parents’ smoking has a small effect on reported cough, more coughs when parents smoke. Children's smoking has a very large effect, more coughs when child smokes once per week or more.

Each effect appears to be independent of the other.

Back to Cross-sectional studies.

This page maintained by Martin Bland.
Last updated: 27 July, 2015.