Accuracy of ovarian cancer ICD-10 diagnosis in a Danish population-based hospital discharge registry

Objective: We estimated the accuracy of ICD-10 diagnosis of ovarian cancer in a Danish discharge registry (HDR) by comparing it with Cancer Registry data (DCR).

Study design and setting: Patients (N=489) living in North Jutland County, Denmark with ovarian cancer or borderline tumour registered in the HDR or the DCR. We estimated the completeness and positive predictive value (PPV) of ovarian cancer discharge diagnosis. Mortality rates were constructed for both registries.

Results: The completeness in the HDR for ovarian cancer was 96% (95% confidence interval [CI]: 94%-98%) and PPV was 87% (95% CI: 85%-90%). 87 (18%) of the patients coded with ovarian cancer in the HDR had borderline tumours. When borderline tumours were excluded from the DCR, the PPV declined to 69% and the completeness did not change. The mortality rate ratio for ovarian cancer registered in the HDR compared to the DCR was 1.08 (95% CI: 0.90-1.29).

Conclusion: The discharge data (ICD-10) had some misclassification, but can be a valuable tool in assessment of the prognosis of ovarian cancer.

Epidemiology; Ovarian neoplasm; ICD-10 diagnosis; Data quality

[1] Bray F., Sankila R., Ferlay J., Parkin D.M.: "Estimates of cancer incidence and mortality in Europe in 1995". Eur. J. Cancer, 2002, 38, 99.

[2] National Board of Health: "Cancer registret 2000, forel0b1g opg,lrelse". In: Nye tal fra Sundhedsstyrelsen, 2004, 8.

[3] "Kra:ft i a:ggestokkene i tal". 1999. URL: http://www.cancer dk/ alt +om+kraeft/kraeftsy gdomme/ aeggesto k/kraeft + i +aegges tok kene+i+tal.asp.

[4] S,lrensen H.T., Sabroe S., Olsen J.: "A framework for evaluation of secondary data sources for epidemiological research". Int. J. Epidemiol., 1996, 25, 435.

[5] Baron J.A., Weiderpass E.: "An Introduction to epidemiological research with medical databases". Ann. Epidemiol., 2000, 10, 200.

[6] SØrensen H.T.: "Regional administrative health registries as a resource in clinical epidemiology. A study of options, strengths, limitations and data quality provided with example of use.". Int. J Risk Safety Med., 1997, 10, 1.

[7] Kjaergaard J., Clemmensen I.H., Storm H.H.: "Validity and completeness of registration of surgically treated malignant gynaecological diseases in the Danish National Hospital Registry". J. Epidemiol. Biostat., 2001, 6, 387.

[8] Dueholm M., Rokkones E., Lofgren M., Harkki P., Arason G "Nordic gynecologists'opinion on quality assessment registers" Acta Obstet. Gynecol. Scand., 2004, 83, 563.

[9] Gunnarsson U.: "Quality assurance in surgical oncology. Colorectal cancer as an example." Eur. J. Surg. Oneal., 2003, 29, 89.

[10] Gunnarsson U., Seligsohn E., Jestin P., Pahlman L.: "Registration and validity of surgical complications in colorectal cancer surgery". Br. J. Surg., 2003, 90, 454.

[11] Andersen T.F., Madsen M., Jorgensen J., Mellemkjoer L., Olsen J.H.:'The Danish National Hospital Register. A valuable source of data for modern health sciences". Dan. Med. Bull., 1999, 46, 263.

[12] Szklo M., Nieto F.J.: "Sensitivity, specificity, and percent agreement". In: J. Colilla (ed.), Epidemiology Beyond the Basics, Gaithersburg, Aspen Publishers, Inc., 2000, 452.

[13] Kjaergaard J., Clemmensen I.H., Thomsen B.L., Storm H.H "Validity of diagnoses and of operations for nonmalignant gynecological conditions in the Danish National Hospital Registry". J. Clin. Epidemiol., 2002, 55, 137.

[14] Mukherjee A.K., Leck I., Langley FA., Ashcroft C.: 'The completeness and accuracy of health authority and cancer registry records according to a study of ovarian neoplasms". Public Health, 1991, 105, 69.

[15] Tingulstad S., Halvorsen T., Norstein J., Hagen B., Skjeldestad FE.: "Completeness and accuracy of registration of ovarian cancer in the cancer registry of Norway". Int. J. Cancer, 2002, 98, 907.

[16] MacDonald N., Sibley K., Rosenthal A., Menon U., Jayarajah A., Oram D. et al.: "A Comparison of national cancer registry and direct follow-up in the ascertainment of ovarian cancer". Br. J. Cancer, 1999, 80, 1826.

[17] Storm H.H.: "Completeness of cancer registration in Denmark 1943-1966 and efficacy of record linkage procedures". Int. J. Epidemiol., 1988, 17, 44.

[18] Jensen A.R., Overgaard J., Storn仆{.H.: "Validity of breast cancer 10 the Danish Cancer Registry. A study based on clinical records from one County in Denmark". Eur. J. Cancer Prev., 2002, 11, 359.

[19] Brenner H., Savitz D.A.: "The effects of sensitivity and specificity of case selection on validity, sample size, precision, and power in hospital- based case-control studies".Am. J. Epidemiol., 1990, 132, 181.