Do coder characteristics influence validity of ICD-10 hospital discharge data?
BACKGROUND
Administrative data are widely used to study health systems and make important health policy decisions. Yet little is known about the influence of coder characteristics on administrative data validity in these studies. Our goal was to describe the relationship between several measures of validity in coded hospital discharge data and 1) coders' volume of coding (> or = 13,000 vs. <13,000 records), 2) coders' employment status (full- vs. part-time), and 3) hospital type.


METHODS
This descriptive study examined 6 indicators of face validity in ICD-10 coded discharge records from 4 hospitals in Calgary, Canada between April 2002 and March 2007. Specifically, mean number of coded diagnoses, procedures, complications, Z-codes, and codes ending in 8 or 9 were compared by coding volume and employment status, as well as hospital type. The mean number of diagnoses was also compared across coder characteristics for 6 major conditions of varying complexity. Next, kappa statistics were computed to assess agreement between discharge data and linked chart data reabstracted by nursing chart reviewers. Kappas were compared across coder characteristics.


RESULTS
422,618 discharge records were coded by 59 coders during the study period. The mean number of diagnoses per record decreased from 5.2 in 2002/2003 to 3.9 in 2006/2007, while the number of records coded annually increased from 69,613 to 102,842. Coders at the tertiary hospital coded the most diagnoses (5.0 compared with 3.9 and 3.8 at other sites). There was no variation by coder or site characteristics for any other face validity indicator. The mean number of diagnoses increased from 1.5 to 7.9 with increasing complexity of the major diagnosis, but did not vary with coder characteristics. Agreement (kappa) between coded data and chart review did not show any consistent pattern with respect to coder characteristics.


CONCLUSIONS
This large study suggests that coder characteristics do not influence the validity of hospital discharge data. Other jurisdictions might benefit from implementing similar employment programs to ours, e.g.: a requirement for a 2-year college training program, a single management structure across sites, and rotation of coders between sites. Limitations include few coder characteristics available for study due to privacy concerns.
Hennessy
Deirdre A
DA
Department of Community Health Sciences, University of Calgary, 3rd Floor TRW Building, 3280 Hospital Drive NW, Calgary T2N 4Z6, Alberta, Canada.
Quan
Hude
H
Faris
Peter D
PD
Beck
Cynthia A
CA
D002170:Canada; D005260:Female; D005568:Forms and Records Control / Q000592:standards*; D006801:Humans; D038801:International Classification of Diseases / Q000592:standards*; D008297:Male; D008499:Medical Records / Q000592:standards; D008875:Middle Aged; D010351:Patient Discharge / Q000706:statistics & numerical data*; D015203:Reproducibility of Results; D012189:Retrospective Studies
J Clin Epidemiol. 1996 Dec;49(12):1429-33
8991959
Stat Med. 2003 May 15;22(9):1551-70
12704615
Med Care. 2002 Aug;40(8):675-85
12187181
BMC Med Res Methodol. 2009 Jan 21;9:5
19159474
Journal (Inst Health Rec Inf Manag). 2003 Jun;44(2):8-14
12868220
Med Care. 2005 Nov;43(11):1130-9
16224307
Perspect Health Inf Manag. 2007 Apr 16;4:3
18066353
Med Care. 2005 Feb;43(2):182-8
15655432
J Clin Epidemiol. 2004 Apr;57(4):366-72
15135837
Bull World Health Organ. 2004 Dec;82(12):904-13
15654404
J Oncol Manag. 2002 Nov-Dec;11(6):20-6
12502289
Int J Med Inform. 2008 Jan;77(1):50-7
17185030
J Am Med Rec Assoc. 1986 Nov;57(11):29-38
10280223
Med Care. 2004 Aug;42(8):801-9
15258482
Health Serv Res. 2008 Aug;43(4):1424-41
18756617
Health Serv Res. 2005 Oct;40(5 Pt 2):1620-39
16178999
BMC Health Serv Res. 2006 Jun 15;6:77
16776836
Int J Qual Health Care. 1999 Jun;11(3):209-13
10435841
J Chronic Dis. 1987;40(5):373-83
3558716
Can J Aging. 2005 Spring;24 Suppl 1:153-70
16080132
Health Inf Manag. 2008;37(1):25-37
18245862
J Health Care Finance. 2003 Summer;29(4):29-42
12908652
Med Care. 2000 Aug;38(8):796-806
10929992
Med Care. 1998 Jan;36(1):8-27
9431328
Ann Intern Med. 1988 Nov 1;109(9):745-51
3142326
J Clin Epidemiol. 1994 Nov;47(11):1245-51
7722560