TY  - RPRT
TI  - Epidemiology research.
AU  - Jon Nicholl
AU  - Mike Campbell
PY  - 2002
DO  - 10.1016/s0140-6736(02)09476-x
UR  - https://pubmed.ncbi.nlm.nih.gov/12133686/
ID  - 12133686
ER  -