TY  - RPRT
TI  - Confounding in epidemiological studies.
AU  - A N Phillips
AU  - G Davey Smith
PY  - 1993
DO  - 10.1136/bmj.306.6870.142-b
UR  - https://pubmed.ncbi.nlm.nih.gov/8435623/
ID  - 8435623
ER  -