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  • Publication # 13-RA009

Hospital admission codes are useful for identifying cases of pneumonia

Patient Safety and Quality

Combining hospitalization dates with diagnostic codes can validate hospital admissions for community-acquired pneumonia, according to a new study. The researchers also compared hospital admission dates recorded into a primary care database with the actual dates patients were admitted. This approach performed well in identifying patients with pneumonia and the timing of their admissions. 

The study evaluated hospital admission data in a United Kingdom primary care electronic medical record database. Using diagnosis and hospitalization codes, the researchers identified patients who were admitted for pneumonia within 30 days after an outpatient visit for an acute respiratory infection. Chart reviews of the patients’ primary care medical records were then conducted on 59 randomly selected patients to confirm if they actually had documentation of a hospital admission with a diagnosis of pneumonia and, if so, their true admission dates. 

Of the 59 patients, 52 were confirmed hospitalizations; one admission was not for pneumonia. The positive predictive value of using the hospitalization codes to identify pneumonia admissions was 86 percent. Of the 52 validated hospitalizations, 50 were admitted within 14 days of the admission date recorded in the electronic database. Sixteen of the 52 patients admitted for pneumonia had their true hospital discharge date as the recorded admission date in the database. The researchers suggest that the accuracy of admission dates may be better for patients with shorter hospitalizations. 

The study was supported in part by AHRQ (HS16946). See "Accuracy of pneumonia hospital admissions in a primary care electronic medical record database," by Sharon B. Meropol, M.D., Ph.D. and Joshua P. Metlay, M.D., Ph.D., in Pharmacoepidemiology and Drug Safety 21, pp. 659-665, 2012.


Page last reviewed June 2013
Internet Citation: Hospital admission codes are useful for identifying cases of pneumonia: Patient Safety and Quality. June 2013. Agency for Healthcare Research and Quality, Rockville, MD.


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