ICD-10 codes are a valid tool for identification of pneumonia in hospitalized patients aged > or = 65 years.
This study examines the validity of using ICD-10 codes to identify hospitalized pneumonia cases. Using a case-cohort design, subjects were randomly selected from monthly cohorts of patients aged > or = 65 years discharged from April 2000 to March 2002 from two large tertiary Australian hospitals. Cases had ICD-10-AM codes J10-J18 (pneumonia); the cohort sample was randomly selected from all discharges, frequency matched to cases by month. Codes were validated against three comparators: medical record notation of pneumonia, chest radiograph (CXR) report and both. Notation of pneumonia was determined for 5098/5101 eligible patients, and CXR reports reviewed for 3349/3464 (97%) patients with a CXR. Coding performed best against notation of pneumonia: kappa 0.95, sensitivity 97.8% (95% CI 97.1-98.3), specificity 96.9% (95% CI 96.2-97.5), positive predictive value (PPV) 96.2% (95% CI 95.4-97.0) and negative predictive value (NPV) 98.2% (95% CI 97.6-98.6). When medical record notation of pneumonia is used as the standard, ICD-10 codes are a valid method for retrospective ascertainment of hospitalized pneumonia cases and appear superior to use of complexes of symptoms and signs, or radiology reports.
Skull
S A
SA
Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Parkville, Victoria, Australia. saskull@unimelb.edu.au
Andrews
R M
RM
Byrnes
G B
GB
Campbell
D A
DA
Nolan
T M
TM
Brown
G V
GV
Kelly
H A
HA
D000368:Aged; D000369:Aged, 80 and over; D001315:Australia / Q000453:epidemiology; D005260:Female; D006761:Hospitals; D006801:Humans; D038801:International Classification of Diseases / Q000706:statistics & numerical data*; D008297:Male; D008499:Medical Records / Q000706:statistics & numerical data; D011014:Pneumonia / Q000453:epidemiology*; D011159:Population Surveillance / Q000379:methods*; D011237:Predictive Value of Tests; D013902:Radiography, Thoracic / Q000706:statistics & numerical data; D012680:Sensitivity and Specificity