TY - STAND AU - J. Kaye AU - H. Jick BT - Bmj DO - 10.1136/bmj.326.7386.424 M1 - 7386 PY - 2003 SP - 424 EP - 5 T2 - Bmj TI - Incidence of erectile dysfunction and characteristics of patients before and after the introduction of sildenafil in the United Kingdom: cross sectional study with comparison patients VL - 326 SN - 0959-8138 ER -