Evaluation of Electronic Medical Record Administrative Data Linked Database (EMRALD)
Published Online: January 14, 2014
Karen Tu, MD, MSc; Tezeta F. Mitiku, BSc, MSc; Noah M. Ivers, MD; Helen Guo, BSc, MSc; Hong Lu, PhD; Liisa Jaakkimainen, MD, MSc; Doug G. Kavanagh, BSEng, MD; Douglas S. Lee, MD, PhD; and Jack V. Tu, MD, PhD
Although the United States and Canada have historically lagged behind other industrialized countries in the adoption of electronic medical records (EMRs) in primary care,1 with the introduction of the Health Information Technology for Economic and Clinical Health Act in 2009 in the United States2 and the establishment of Canada Health Infoway3 and provincial EMR adoption support programs in Canada, the uptake of EMRs in both countries is rapidly increasing.4 This development, especially in primary care physician practices, has resulted in a new, potentially rich source of clinical information not only for point-of-care clinical practice but also for secondary purposes such as research and quality performance evaluation.
Because of its single-payer healthcare system, Canada has comprehensive health-related administrative databases that cover the entire population. Complete, provincewide, population-level administrative databases have been shown to be highly accurate in capturing hospitalizations and prescriptions for Ontario residents 65 years and older.5 Also in these databases, physician billing data accurately capture frequency of patient encounters, but the depth and details of patient clinical encounters are unavailable. Indeed, a previous study in the United States found that EMR data in community health centers were more complete than Medicaid claims data for assessing diabetes preventive care.6
Because use of primary care EMR data in Canada for secondary purposes is in its relative infancy, we set out to determine the completeness and comprehensiveness of the EMR data compared with administrative data.
We developed the Electronic Medical Record Administrative data Linked Database (EMRALD) at the Institute for Clinical Evaluative Sciences (ICES). The Institute for Clinical Evaluative Sciences is a “prescribed entity” under provincial privacy legislation and thus is able to collect individual-level patient health information without patient consent based on policies and procedures in place to protect patient privacy and confidentiality.7 EMRALD was developed using data from family physicians (FPs) in Ontario using Practice Solutions EMR, the market-leading EMR software vendor in Ontario.8 All clinically relevant data are extracted from the participating physician’s EMR and each patient is anonymously linked, using their scrambled health card number, to the health-related administrative databases for the province of Ontario housed at ICES.
Physicians participate on a completely voluntary basis and are required to have had their EMR a minimum of 2 years to ensure that the EMR is adequately populated. Over the past decade Ontario has undergone major primary care reform such that the majority of all FPs in the province practice under one of the reform models that require “rostering” of patients (identification of patients with the 1 primary care provider who is most responsible for their care).9 All of the EMRALD FPs practice under one of the various primary care reform models of care. This analysis was confined to data that were captured in 2008 for rostered patients of participating FPs who had at least 1 visit to their physician in the 2 years before January 1, 2008.
Family Physician Clinic Visits
To determine the capture of all FP visits by patients rostered to EMRALD physicians (regardless of whether the visit was to an EMRALD physician), FP outpatient visits billed to the Ontario Health Insurance Plan (OHIP) physician billing database were compared with visits recorded in the EMR to determine the capture of FP visits by patients rostered to EMRALD physicians. Visit comparison between OHIP and EMRALD was confined to EMRALD physician OHIP visits only, to assess how completely EMRALD physicians were documenting patient visits within their EMR.
Specialist Consultations and Hospitalizations
To determine the capture of specialist visits and hospitalizations within EMRALD, OHIP billings by specialists performed in an office setting for an initial consultation and hospitalizations, as recorded in the Canadian Institute for Health Information Discharge Abstract Database, were compared with consultation letters and hospital discharge summaries in EMRALD within 14 days and within 30 days of the specialist billing date or the hospital discharge date.
A frequency count of OHIP laboratory fee codes identified the 20 most common laboratory tests ordered. Comparisons were made between the laboratory tests recorded on the same day in EMRALD and in OHIP.
The EMR records when a drug is prescribed to the patient by the EMR physician, and the Ontario Drug Database (ODB) records when a drug was dispensed at a pharmacy (regardless of the prescriber). The EMR may also list drugs prescribed to a patient by other providers (ie, specialists), but only if such data are manually updated by the EMR-using physician; thus, the EMR is variably populated with these data. The prescription field within EMRALD and the prescriptions dispensed in ODB in 2008 were used to compile 2 drugs lists for the top 50 dispensed Canadian medications,10 grouped into 7 clinical categories. The 2 lists for each patient were compared. This analysis was confined to patients 65 years and older as of January 1, 2008, as the ODB only captures drugs universally for all Ontario residents 65 years and older.
Match rates were calculated for all parameters of comparison by calculating the mean match rate and standard deviation (SD) for all the clinics, giving each clinic equal weighting regardless of size.
This study received ethics approval from Sunnybrook Health Sciences Research Ethics Board.
Overall, there were 56,107 patients with an average age of 39.7 years from 54 physicians practicing in 15 geographically distinct clinics. The mean years since graduation of the physicians was 19.3 years (SD = 10.4 years). Seventy percent of the physicians were in urban practice, 56% were male, and 98% were in group practice. The average duration of time on the EMR was 4.5 years (SD = 2.6 years).
Family Physician Visits
PDF is available on the last page.