共 21 条
[2]
Centers for Disease Control and Prevention (CDC), 2001, MMWR Morb Mortal Wkly Rep, V50, P919
[3]
Centers for Disease Control and Prevention (CDC), 2003, MMWR Morb Mortal Wkly Rep, V52, P88
[10]
Fleiss JL, 1981, STAT METHODS RATES P