The Institute for Clinical Evaluative Sciences: 20 Years and Counting

Abstract

T he management of hypertension has traditionally been based on the measurement of blood pressure (BP) in the office using manual devices, such as the mercury sphygmoma-nometer. Manual BP measurement is associated with numerous sources of error, the most important of which relate to human behavior. In the office setting, many patients become anxious, health professionals frequently do not follow proper BP measurement technique, and the presence of a nurse or physician leads to conversation, which increases BP. Also, the phasing out of the mercury sphygmomanometer because of concerns about its potential adverse effects on the environment and human health provides further motivation to reexamine the role of manual BP in clinical practice. In recent years, the pre-eminence of office BP has been challenged by the widespread use of 24-hour ambulatory BP monitoring (ABPM) and self-measurement of BP in the home. The well documented advantages of ABPM 1 and home BP 2 in evaluating the benefits of antihypertensive therapy for individual patients has led to major changes in recent guidelines for the diagnosis of hypertension. ABPM and home BP have been advocated as the methods of choice for determining the BP status of patients, 3-5 whereas manual office BP is being replaced by electronic oscillometric sphygmomanom-eters, most of which are activated by the office staff. Although these semiautomated devices eliminate some of the errors associated with manual BP measurement, the presence of an observer may still provoke inaccurate BP readings. 6,7 This limitation of semiautomated devices has been overcome by the development of accurate oscillometric sphygmo-manometers specifically designed for professional use, which take multiple BP readings automatically with the patient resting quietly and alone, 8 now referred to as automated office BP (AOBP). Numerous studies comparing AOBP to awake ambulatory BP and home BP have shown that AOBP produces Abstract-The risk of cardiovascular events in relation to blood pressure is largely based on readings taken with a mercury sphygmomanometer in populations which differ from those of today in terms of hypertension severity and drug therapy. Given replacement of the mercury sphygmomanometer with electronic devices, we sought to determine the blood pressure threshold for a significant increase in cardiovascular risk using a fully automated device, which takes multiple readings with the subject resting quietly alone. Participants were 3627 community-dwelling residents aged >65 years untreated for hypertension. Automated office blood pressure readings were obtained in a community pharmacy with subjects seated and undisturbed. This method for recording blood pressure produces similar readings in different settings, including a pharmacy and family doctor's office providing the above procedures are followed. Subjects were followed for a mean (SD) of 4.9 (1.0) years for fatal and nonfatal cardiovascular events. Adjusted hazard ratios (95% confidence intervals) were computed for 10 mm Hg increme...

Motor vehicle crashes during pregnancy and cerebral palsy during infancy: a longitudinal cohort analysis

“…We conducted a retrospective longitudinal population-based cohort study using data sets from the Institute for Clinical Evaluative Sciences (ICES). 32 These data sets integrate information from medical encounters by patients throughout the Ontario healthcare system as covered by the universal health insurance plan. 33 This plan provided all-inclusive access to care with no cost to patients for emergency or prenatal treatments, thereby providing comprehensive longitudinal patient data for analysis.…”

Administrative health data in Canada: lessons from history

“…David Naylor and Jack Williams of the Clinical Epidemiology Unit and Research program at Toronto responded in 1991 with a proposal for ICES, which would use administrative health data from the Ministry of Health for population-level research [18]. Their proposal was strengthened by the Ontario Health Insurance Plan’s recent issue of health cards to residents, which would allow for patients to be tracked by unique identifiers (e.g., age, medication) [18]. The proposal was quickly funded with a $20-million commitment from the Province [17].…”

“…Today, ICES holds de-identified, linkable data on 13 million of Ontario’s residents, under the Personal Health Information Protection Act, has 4 satellite sites in medical schools across Ontario and established remote access and analysis system for users [18–20]. ICES continues to operate within arm’s length of the Ontario Government and partners with numerous national/provincial programs to produce work that informs policy and expands the capacity for research in Canada [19].…”

Comorbidities Before and After the Diagnosis of Rheumatoid Arthritis: A Matched Longitudinal Study

“…The study was a matched longitudinal cohort study using individual‐level administrative data. Data were housed at the ICES (formerly the Institute for Clinical Evaluative Sciences (19)), a nonprofit research institute funded by the Ontario Ministry of Health, which holds administrative data for all health care billings from a publicly funded single payor, meaning all patients under study had identical health insurance coverage.…”