Elwood, J. Mark <br/><br/>
Critical appraisal of epidemiological studies and clinical trials 

 - 3rd ed. 
 - Oxford :  Oxford University Press  2007 
 - (pbk) 
 - Oxford medical publications .
<br/><br/><label>ISBN: </label>0198529554 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Medical Statistics<br/>Epidemiology<br/>Medicine-Information Sources<br/>Research-Health Services