@article{doi:10.1001/archinternmed.2009.250,
author = {Groenwold RH and Donders AT and van der Heijden GG and Hoes AW and Rovers MM},
title = {COnfounding of subgroup analyses in randomized data},
journal = {Archives of Internal Medicine},
volume = {169},
number = {16},
pages = {1532-1534},
year = {2009},
doi = {10.1001/archinternmed.2009.250},
URL = { + http://dx.doi.org/10.1001/archinternmed.2009.250},
eprint = {/data/Journals/INTEMED/22600/ibr90001_1532_1534.pdf}
}