Demets, D L <br/><br/>
Group sequential procedures: calendar versus information time.  [electronic resource] 

 -  Statistics in medicine  Oct 1989 
 - 1191-8 p.  digital 
<br/><br/> Publication Type: Comparative Study; Journal Article; Research Support, U.S. Gov't, P.H.S. 
<br/><br/><label>ISSN: </label>0277-6715 
<br/><br/><label>Standard No.: </label>10.1002/sim.4780081003  doi 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Algorithms<br/>Chronology as Topic<br/>Clinical Protocols--standards<br/>Clinical Trials as Topic--standards<br/>Computer Simulation<br/>Data Collection<br/>Group Structure