Validation of Carotid Artery Revascularization Coding in Ontario Health Administrative Databases

Abstract

Purpose: The positive predictive value (PPV) of carotid endarterectomy (CEA) and carotid artery stenting (CAS) procedure and post-operative complication coding were assessed in Ontario health administrative databases.Methods: Between 1 April 2002 and 31 March 2014, a random sample of 428 patients were identified using Canadian Classification of Health Intervention (CCI) procedure codes and Ontario Health Insurance Plan (OHIP) billing codes from administrative data. A blinded chart review was conducted at two high-volume vascular centers to assess the level of agreement between the administrative records and the corresponding patients' hospital charts. PPV was calculated with 95% confidence intervals (CIs) to estimate the validity of CEA and CAS coding, utilizing hospital charts as the gold standard. Sensitivity of CEA and CAS coding were also assessed by linking two independent databases of 540 CEA-treated patients (Ontario Stroke Registry) and 140 CAS-treated patients (single-center CAS database) to administrative records.Results: PPV for CEA ranged from 99% to 100% and sensitivity ranged from 81.5% to 89.6% using CCI and OHIP codes. A CCI code with a PPV of 87% (95% CI, 78.8-92.9) and sensitivity of 92.9% (95% CI, 87.4-96.1) in identifying CAS was also identified. PPV for post-admission complication diagnosis coding was 71.4% (95% CI, 53.7-85.4) for stroke/transient ischemic attack, and 82.4% (95% CI, 56.6-96.2) for myocardial infarction.Conclusions: Our analysis demonstrated that the codes used in administrative databases accurately identify CEA and CAS-treated patients. Researchers can confidently use administrative data to conduct population-based studies of CEA and CAS.

Impact of Clinical Trial Results on the Temporal Trends of Carotid Endarterectomy and Stenting From 2002 to 2014

“…To mitigate this risk, we used procedure codes that have been previously validated. 19 Second, our databases did not specify if prior neurological events occurred on the ipsilateral or contralateral side of the carotid revascularization procedure—this may overestimate the actual number of patients with symptomatic carotid-artery stenosis because patients with prior contralateral strokes may have been incorrectly captured as symptomatic patients. Third, the temporal trends in carotid revascularization we report are limited to the province of Ontario, and these findings may not be generalizable to other settings.…”

“…We used previously validated Canadian Classification of Health Intervention procedure codes to identify patients treated with carotid endarterectomy (1JE57Lx; positive predictive value, 99%; sensitivity, 90%) and carotid-artery stenting (1JE50x; positive predictive value, 87%; sensitivity, 93%). 19 In addition, we established the following patient baseline characteristics: age, sex, region, treating institution type, carotid-artery symptoms, and operator specialty. Symptomatic carotid-artery stenosis was defined as a previous hospital admission or an emergency department visit within the last 6 months with a diagnosis of ischemic stroke or transient ischemic attack.…”

Regional differences in use of endoscopic ultrasonography in Ontario: a population-based retrospective cohort study

“…19 The Ontario Health Insurance Plan (OHIP) database contains information as of 1991 on claims billed for physician and laboratory services, including endoscopic procedures. OHIP database diagnostic codes have been shown to have a high positive predictive rate (> 90%) [20][21][22][23] and high specificity (> 85%) [24][25][26][27] but somewhat limited sensitivity (35%-85%). [24][25][26][27] The Registered Persons Database is a roster of OHIP beneficiaries and maintains information on age, sex, postal code and vital statistics for all Ontarians with a valid OHIP number.…”

“…However, OHIP billing data have been shown to be highly accurate for other procedures. [20][21][22][23][24][25][26][27] We attempted to maximize the specificity of the endoscopic ultrasonography codes by excluding procedures not performed by physicians in related health care specialties; however, future validation studies are needed. Second, it is possible that endoscopic ultrasound procedures performed in the earlier years of this cohort were not captured by OHIP billing codes; however, as the study period was designed to begin 2 years after codes for endoscopic ultrasonography were introduced in Ontario, we feel that this is unlikely.…”

Auditory brainstem implant program development

“…Procedural registries have been created in a number of countries and for a variety of types of pathology . These registries typically are publically administered or privately financed, generally with the understanding of a potential public health benefit .…”