Sauerland, Stefan <br/><br/>
An experiment of mailing physician surveys on two different issues in joint or separate mail.  [electronic resource] 

 -  Journal of clinical epidemiology  Oct 2002 
 - 1046-8 p.  digital 
<br/><br/> Publication Type: Clinical Trial; Journal Article; Randomized Controlled Trial 
<br/><br/><label>ISSN: </label>0895-4356 
<br/><br/><label>Standard No.: </label>10.1016/s0895-4356(02)00459-6  doi 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Data Collection--economics<br/>Humans<br/>Physicians<br/>Postal Service<br/>Selection Bias