Validity of hospital discharge data for identifying infants with cardiac defects.
OBJECTIVE
To examine validity of the International Classification of Diseases, 9th Edition, Clinical Modification (ICD-9-CM) codes in discharge data for identifying infants with cardiac defects according to surveillance guidelines.


METHODS
Retrospective medical record review of infants born in 2001 at one hospital in Minneapolis, Minnesota. Infants were identified using ICD-9-CM codes from hospital discharge data, and keywords in medical records.


RESULTS
Of 2,697 children, ICD-9-CM codes identified 66 infants coded with cardiac defects; physician review confirmed 24 had cardiac defects. Only 35 of 85 (41.2%) ICD-9-CM codes accurately reflected the cardiac defect diagnoses. Additional case finding located four infants with five cardiac defects. Sensitivity of ICD-9-CM codes for identifying these infants was 0.857, predictive value positive was 0.364.


CONCLUSIONS
ICD-9-CM codes from hospital discharge data identified most infants with cardiac defects, but many were false positives. ICD-9-CM codes were inaccurate for specific cardiac defects.
Frohnert
Barbara Kathleen
BK
CDC/CSTE Applied Epidemiology Fellow, Minnesota Department of Health, St. Paul, MN 55164-0975, USA.
Lussky
Richard Charles
RC
Alms
Maureen Anne
MA
Mendelsohn
Nancy J
NJ
Symonik
Daniel Michael
DM
Falken
Myron Clifford
MC
D001719:Birth Certificates; D006330:Heart Defects, Congenital / Q000145:classification / Q000175:diagnosis* / Q000453:epidemiology*; D006801:Humans; D007223:Infant; D038801:International Classification of Diseases; D008499:Medical Records / Q000145:classification* / Q000592:standards; D008910:Minnesota / Q000453:epidemiology; D010351:Patient Discharge; D010865:Pilot Projects; D011159:Population Surveillance / Q000379:methods