Song Yun-Mi, Sung Joohon, Lawlor Debbie A, Davey Smith George, Shin Youngsoo, Ebrahim Shah
Department of Family Medicine, Samsung Medical Center, SungKyunKwan University School of Medicine, 50 Irwon-Dong, Gangnam-Gu, Seoul, Korea.
BMJ. 2004 Feb 7;328(7435):324-5. doi: 10.1136/bmj.328.7435.324.