TY  - RPRT
TI  - Increased precision using countermatching in nested case-control studies.
AU  - K Steenland
AU  - J A Deddens
PY  - 1997
DO  - 10.1097/00001648-199705000-00002
UR  - https://pubmed.ncbi.nlm.nih.gov/9115016/
ID  - 9115016
ER  -