@article {Shapiro185, author = {Samuel Shapiro}, title = {Causation, bias and confounding: a hitchhiker{\textquoteright}s guide to the epidemiological galaxy}, volume = {34}, number = {3}, pages = {185--190}, year = {2008}, doi = {10.1783/147118908784734873}, publisher = {British Medical Journal Publishing Group}, issn = {1471-1893}, URL = {https://srh.bmj.com/content/34/3/185}, eprint = {https://srh.bmj.com/content/34/3/185.full.pdf}, journal = {BMJ Sexual \& Reproductive Health} }