Cattaruzzi, C <br/><br/>
Positive predictive value of ICD-9th codes for upper gastrointestinal bleeding and perforation in the Sistema Informativo Sanitario Regionale database.  [electronic resource] 

 -  Journal of clinical epidemiology  Jun 1999 
 - 499-502 p.  digital 
<br/><br/> Publication Type: Journal Article; Multicenter Study 
<br/><br/><label>ISSN: </label>0895-4356 
<br/><br/><label>Standard No.: </label>10.1016/s0895-4356(99)00004-9  doi 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Adult<br/>Aged<br/>Aged, 80 and over<br/>Case-Control Studies<br/>Diagnosis-Related Groups--standards<br/>Duodenal Diseases--classification<br/>Female<br/>Gastrointestinal Hemorrhage--classification<br/>Humans<br/>Intestinal Perforation--classification<br/>Italy<br/>Male<br/>Medical Records Systems, Computerized--classification<br/>Middle Aged<br/>Peptic Ulcer Perforation--classification<br/>Predictive Value of Tests<br/>Retrospective Studies<br/>Stomach Diseases--classification