TY  - RPRT
TI  - Trying to avoid bias in case-control and case-cohort studies.
AU  - Paul G McDonough
PY  - 2003
DO  - 10.1016/j.fertnstert.2003.09.003
UR  - https://pubmed.ncbi.nlm.nih.gov/14667913/
ID  - 14667913
ER  -