Factors Associated with Stroke Coding Quality: A Comparison of Registry and Administrative Data.

BACKGROUND: The International Statistical Classification of Diseases and Related Health Problems, 10th Revision, Australian Modification (ICD-10-AM) codes are commonly used to identify patients with diseases or clinical conditions for epidemiological research. We aimed to determine the diagnostic agreement and factors associated with a clinician-assigned stroke diagnosis in a national registry and the ICD-10-AM codes recorded in government-held administrative data. MATERIALS AND METHODS: Data from 39 hospitals (2009-2013) participating in the Australian Stroke Clinical Registry (AuSCR) were linked and merged with person-level administrative data. The AuSCR clinician-assigned stroke diagnosis was the reference standard. Concordance was defined as agreement between the clinician-assigned diagnosis and the ICD-10-AM codes for acute stroke or transient ischemic attack (TIA) (ICD-10-AM codes: I61-I64, G45.9). Multivariable logistic regression was undertaken to assess factors associated with coded diagnostic concordance. RESULTS: A total of 14,716 patient admissions were included (46% female, 63% ischemic, 14% intracerebral hemorrhage [ICH], 18% TIA and 5% unspecified stroke based on the reference standard). Principal ICD-10-AM code concordance was ICH: 76.7%; ischemic stroke: 72.2%; TIA: 80.2%; unspecified stroke: 50.8%. Factors associated with a greater odds of ischemic stroke concordance included: treatment in a stroke unit (adjusted Odds Ratio, aOR:1.58; 95% confidence interval (CI) 1.37, 1.82); length of stay >4 days (aOR:1.30; 95% CI 1.17, 1.45); and discharge destination other than home (Residential care aOR:1.57; 95% CI 1.24, 1.96; Inpatient rehabilitation aOR:1.63; 95% CI 1.43, 1.86). CONCLUSIONS: Diagnostic concordance varied based on stroke type. Future research to improve the quality of coding for stroke should focus on patients not treated in stroke units or with shorter lengths of stay where documentation in medical records may be limited.

Telephone follow-up was more expensive but more efficient than postal in a national stroke registry.

OBJECTIVE: To compare the efficiency and differential costs of telephone- vs. mail-based assessments of outcome in patients registered in a national clinical quality of care registry, the Australian Stroke Clinical Registry (AuSCR). STUDY DESIGN AND SETTING: The participants admitted to hospital with stroke or transient ischemic attack were randomly assigned to complete a health questionnaire by mail or telephone interview at 3-6 months postevent. Response rate, researcher burden, and costs of each method were compared. RESULTS: Compared with the participants in the mail questionnaire arm (n=277; 50% female; mean age: 70 years), those in the telephone arm (n=282; 45% female; mean age: 68 years) required a shorter time to complete the follow-up (mean difference: 24.2 days; 95% confidence interval [CI]: 15.0, 33.5 days). However, the average cost of completing a telephone follow-up was greater (US$20.87 vs. US$13.86) and had a similar overall response to the mail method (absolute difference: 0.57%; 95% CI: -4.8%, 6%). CONCLUSION: Posthospital stroke outcome data were slower to collect by mail, but the method achieved a similar completion rate and was significantly cheaper to conduct than follow-up telephone interview. Findings are informative for planning outcome data collection in large numbers of patients with acute stroke.