Sackett, David L. Haynes, R. Brain. Guyatt, Gordon H. Tugwell, Peter. <br/><br/>
Clinical epidemiology :a basic science for clinical medicine  

 - 2nd ed. 
 - Boston :  Little, Brown ,  1991 . 
 - xvii, 441 p. :  ill. (some col.) ; 
<br/><br/>Includes index. 
<br/><br/><label>ISBN: </label>0316765996 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Clinical epidemiology.