A.0.5 B.1 C.2 D.3 E.4
A.15% B.16% C.17% D.20% E.25%
A.準(zhǔn)試驗 B.現(xiàn)場試驗 C.臨床試驗 D.病例對照研究 E.社區(qū)干預(yù)試驗