Computer-prompted diagnostic codes.
BACKGROUND
The purpose of this study was to develop and evaluate a computer system that would translate patient diagnoses noted by a physician into appropriate International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes and maintain a patient-specific up-to-date problem list.


METHODS
The intervention consisted of a computerized list (dictionary) of diagnoses, including practice-specific synonyms and abbreviations, linked to their corresponding ICD-9-CM codes. To record the diagnoses for the office visit before the intervention, physicians used International Classification of Health Problems in Primary Care (ICHPPC-2) codes. After the intervention, physicians used their own words or checked previously identified diagnoses on the computer-generated problem list. The computer then identified the correct ICD-9-CM code. Accuracy of coding was compared before and after the new computerized system was implemented.


RESULTS
Visits in which all diagnoses matched increased from 58% to 76% (P < .001) with use of the computer system. Visits in which no computer diagnoses matched the chart decreased from 22% to 8% (P < .001). Errors of omission declined from 38% to 18% (P < .001). Errors of commission decreased from 19% to 11% (P = .006). Overall accuracy increased from 62% to 82% (P < .001).


CONCLUSIONS
Outpatient medical diagnosis coding can be simplified and accuracy improved by using a computerized dictionary of practice-specific diagnoses and synonyms linked to appropriate ICD-9-CM codes. Such a system provides a computer-generated problem list that accurately reflects the chart and assists with prompted coding on subsequent visits.
Yarnall
K S
KS
Department of Community and Family Medicine, Duke University Medical Center, Durham, NC 27710.
Michener
J L
JL
Broadhead
W E
WE
Hammond
W E
WE
Tse
C K
CK
D000043:Abstracting and Indexing / Q000592:standards*; D003933:Diagnosis; D005194:Family Practice; D006801:Humans; D016347:Medical Records Systems, Computerized / Q000145:classification*; D009657:North Carolina; D009819:Office Visits; D010044:Outpatient Clinics, Hospital