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Background Some clinical trials, laboratory experiments, and in vitro studies suggest that lipid-lowering medications predispose a person to traumatic injury. Methods We used population-based administrative database analysis to study adults age 65 years or more over a 5-year interval (n = 1,348,259). Results About 12% of the cohort received a prescription for a lipid-lowering medication and about 88% did not. The two groups had similar distributions of age, gender, and income. Overall, 2,557 (0.2%) were hospitalized for major trauma. Those who received a lipid-lowering medication were 39% less likely to sustain a major trauma than those who did not receive such medication (95% confidence interval, 29 to 47). Similar results were observed after adjustment for age, gender, and income; cardiac and neurologic medications; and lethality. No other cardiac or neurologic medication was associated with an apparent safety advantage. Conclusion Lipid-lowering medications do not lead to a clinically important increase in the absolute risk of major trauma for elderly patients in the community.

Driven by fiscal pressures in the 1990s, Canada's provincial Medicare systems cut inpatient care, expanded community services, and consolidated hospitals under regional authorities in nine of ten provinces. Public confidence has been badly shaken by the transition. No province has successfully integrated services across the continuum of care. Home care and prescription drug coverage vary from province to province. Efforts to reform physician payment have stalled, and capacity to measure and manage the quality of care is generally underdeveloped. Thus, for the next few years, policymakers must stabilize the acute care sector, while cautiously pursuing an agenda of piece-meal reforms.

Objective. To compare the abilities of artificial neural network and logistic regression models to predict the risk of in-hospital mortality after coronary artery bypass graft (CABG) surgery. Methods. Neural network and logistic regression models were developed using a training set of 4,782 patients undergoing CABG surgery in Ontario, Canada, in 1991, and they were validated in two test sets of 5,309 and 5,517 patients having CABG surgery in 1992 and 1993, respectively. Results. The probabilities predicted from a fully trained neural network were similar to those of a “saturated” regression model, with both models detecting all possible interactions in the training set and validating poorly in the two test sets. A second neural network was developed by cross-validating a network against a new set of data and terminating network training early to create a more generalizable model. A simple “main effects” regression model without any interaction terms was also developed. Both of these models validated well, with areas under the receiver operating characteristic curves of 0.78 and 0.77 (p > 0.10) in the 1993 test set. The predictions from the two models were very highly correlated (r = 0.95). Conclusions. Artificial neural networks and logistic regression models learn similar relationships between patient characteristics and mortality after CABG surgery.

Background The usual approach to detecting gestational diabetes mellitus is to screen all pregnant women by measuring their plasma glucose after a 50-g oral glucose load at 24 to 28 weeks' gestation. Women are referred for an oral glucose-tolerance test if the plasma glucose concentration one hour later is >140 mg per deciliter (7.8 mmol per liter). We hypothesized that the efficiency of screening could be enhanced by considering women's risks of gestational diabetes on the basis of their clinical characteristics. Methods We studied 3131 pregnant women who underwent both the screening and the diagnostic tests. We randomly selected data on half the women and used them to derive new screening strategies. We categorized each woman's risk of gestational diabetes mellitus on the basis of her age, body-mass index before pregnancy, and race. We developed strategies that entailed no screening for low-risk women, usual care for intermediate-risk women, and universal screening with lower thresholds — plasma glucose...

Objectives: To examine funding priorities assigned by health ministry officials when choosing between clinical programs that offer similar overall benefits distributed in different ways (e.g. large gains for a few versus small gains for many), and to compare the relative magnitude of any distributional bias to age biases. Methods: A survey consisting of paired hypothetical health care programs was mailed to the 135 most senior officials of the Health Ministry in Ontario, Canada (population 11.5 million). Respondents were asked to assume they were members of a panel allocating a fixed sum of money to one of two programs in each pair. All program descriptions included the number of persons affected each year by a given disease and the average survival gains from the hypothetical programs. Some scenarios also mentioned the side-effects associated with programs and/or the average age of the beneficiaries. Results: Four respondents had retired/died. Of 131 eligible respondents, 80/131 (61%) provided usable responses. Asked to choose between providing large benefits to a few citizens and small benefits to a great many, 23% (95% CI: 14%, 33%) of respondents were unable to decide, but 55.8% (95% CI: 47%, 70%) favored providing large benefits to fewer patients. Eliminating the 23% unable to decide, 47/62 or 76% (CI: 63%, 86%) expressed a distributional preference. With a smaller distributional discrepancy, indecision increased, with 35% of respondents having no preference and the remainder split almost evenly between the two programs. Other scenarios showed that health officials' pro-youth biases were only slightly larger than their distributional preferences and that distributional preferences were magnified when combined with minor differences in average ages of beneficiaries. Conclusions: A substantial minority of health care decision-makers had difficulty choosing between programs with similar overall gains and distributional differences — a result consistent with the utilitarian assumptions of cost-effectiveness analysis. However, when distributional differences were large, decision-makers clearly favored large gains for a few beneficiaries rather than small gains for many. Policy analysts should explicitly weigh distributional issues along with aggregate health gains when addressing resource allocation problems.

OBJECTIVES--To develop, from simple clinical factors, criteria to identify appropriate patients for referral to a surgeon for consideration for arthroplasty, and to rank them in the queue once surgery is agreed. DESIGN--Delphi process, with a panel including orthopaedic surgeons, rheumatologists, general practitioners, epidemiologists, and physiotherapists, who rated 120 case scenarios for appropriateness and 42 for waiting list priority. Scenarios incorporated combinations of relevant clinical factors. It was assumed that queues should be organised not simply by chronology but by clinical and social impact of delayed surgery. The panel focused on information obtained from clinical histories, to ensure the utility of the guidelines in practice. Relevant high quality research evidence was limited. SETTING--Ontario, Canada. MAIN MEASURES--Appropriateness ratings on a 7-point scale, and urgency rankings on a 4-point scale keyed to specific waiting times. RESULTS--Despite incomplete evidence panellists agreed on ratings in 92.5% of appropriateness and 73.8% of urgency scenarios versus 15% and 18% agreement expected by chance, respectively. Statistically validated algorithms in decision tree form, which should permit rapid estimation of urgency or appropriateness in practice, were compiled by recursive partitioning. Rating patterns and algorithms were also used to make brief written guidelines on how clinical factors affect appropriateness and urgency of surgery. A summary score was provided for each case scenario; scenarios could then be matched to chart audit results, with scoring for quality management. CONCLUSIONS--These algorithms and criteria can be used by managers or practitioners to assess appropriateness of referral for hip or knee replacement and relative rankings of patients in the queue for surgery.

The purpose of this study was to describe the life-sustaining treatment preferences of dialysis patients and to compare the acceptability of two generic and a disease-specific advance directive (AD). Of 532 potentially eligible hemodialysis patients, 95 (17.9%) participated in the study. These patients completed two generic (the Centre for Bioethics Living Will and the Medical Directive) and one disease-specific (the Dialysis Living Will) AD in a randomized cross-over trial. Treatment preferences were measured by using the Centre for Bioethics Living Will. Acceptability of the AD was measured by using a 13-item advance directive acceptability questionnaire (ADAQ) for each AD, and the advance directive choice questionnaire (ADCQ) to elicit participants' preferred AD. Twenty-five percent of the participants wanted to continue dialysis in case of severe stroke, 19% in severe dementia, and 14% in permanent coma. Averaged across treatments, proportions of participants wanting treatment in various health states were: current health (86%), mild stroke (84%), moderate stroke (60%), severe stroke (21%), mild dementia (78%), moderate dementia (51%), severe dementia (14%), terminal illness (41%), and permanent coma (10%). Averaged across health states, proportions of participants wanting various types of treatment were: dialysis (58%), antibiotics (53%), transfusion (53%), surgery (48%), cardiopulmonary resuscitation (48%), respirator (47%), and tube feeding (41%). Mean ADAQ scores were: Dialysis Living Will, 71%; Centre for Bioethics Living Will, 70%; and Medical Directive, 60% (F = 8.27, P < 0.001 (repeat measures analysis of variance); the Dialysis Living Will and Centre for Bioethics Living Will scored significantly higher than the Medical Directive). The proportion of participants who said they would choose to complete each AD was: Dialysis Living Will, 28%; Centre for Bioethics Living Will, 38%; Medical Directive, 31%; and unsure, 3% (chi 2 = 1.465, df = 2, P = 0.48). In conclusion, twenty-five percent or less of hemodialysis patients want to continue dialysis in three specific health states: severe stroke, severe dementia, and permanent coma. Health states and illness severity, far more than treatment descriptions, influence preferences. Dialysis patients should be offered a generic AD, and some generic AD are more acceptable than others. Only a minority of dialysis patients will complete any AD, but the completion of written AD forms is only one element in the process of advance care planning.

Background A multicenter population-based study was conducted to develop and validate a risk index for mortality, intensive care unit (ICU) length of stay, and postoperative length of stay after cardiac surgery. Methods and Results Data were collected from 13 098 patients undergoing cardiac surgery between April 1, 1991, and March 31, 1993, at all nine adult cardiac surgery institutions in Ontario, Canada. A six-variable risk index (age, sex, left ventricular function, type of surgery, urgency of surgery, and repeat operation) was developed using logistic regression analysis to predict in-hospital mortality, ICU stay in days, and postoperative stay in days after cardiac surgery in a derivation set of 6213 patients who had cardiac surgery during fiscal year 1991 (April 1, 1991, to March 31, 1992). The index predicted mortality, prolonged ICU stay (≥6 days), and prolonged postoperative length of stay (≥17 days) after cardiac surgery with areas under the receiver-operating characteristic (ROC) curve of 0.75, 0.66, and 0.69, respectively, in an independent validation set of 6885 patients who had cardiac surgery during fiscal year 1992 (April 1, 1992, to March 31, 1993). Increasing risk scores were associated with greater mortality rates and longer ICU and postoperative stays at all nine institutions. Conclusions Mortality, ICU length of stay, and postoperative length of stay after cardiac surgery can be predicted using a simple six-variable risk index. The index has potential application as a risk stratification tool for comparing patient outcomes and resource use among different hospitals and surgeons.

BACKGROUND Thrombolytic therapy reduces mortality after acute myocardial infarction, even when treatment is initiated relatively late after onset of symptoms. The mechanism underlying this survival benefit is incompletely understood. METHODS AND RESULTS In a prospectively designed ancillary study of a randomized, placebo-controlled trial of late thrombolytic therapy (LATE), the signal-averaged (SA) ECG was recorded before hospital discharge in an effort to assess the effect of thrombolytic therapy on arrhythmia substrate. Three hundred ten patients were enrolled at 23 participating sites; 160 patients received placebo, and 150 patients received recombinant tissue-type plasminogen activator (rTPA) therapy 6 to 24 hours after onset of symptoms. Compared with placebo, rTPA tended to reduce the frequency of SAECG abnormality (filtered QRS duration > 120 milliseconds) by 37% (95% CI, -64%, +6%; P = .087) and the filtered QRS duration (105.7 +/- 13.8 versus 108.8 +/- 14.6 milliseconds, P = .05). In the prespecified subgroup of 185 patients with ST elevation on the qualifying ECG, rTPA resulted in a 52% reduction (95% CI, 4% to 77%, P = .011) of SAECG abnormality and a shorter filtered QRS duration (105.7 +/- 10.9 versus 110.7 +/- 15.9 milliseconds, P = .01). No benefit was seen in patients without ST elevation on ECG. CONCLUSIONS Late thrombolytic therapy produced a more stable electrical substrate, which probably represents an important mechanism of mortality benefit.

The growing burden of prescription drug costs has focused attention on factors which influence physicians’ prescribing decisions. We hypothesised that third party coverage of prescription costs would elicit selection of expensive drugs, but that this tendency could be moderated by price reminders. In a mailed survey, primary care physicians throughout Ontario (n = 1072) were provided with the clinical scenario of a patient with an infectious exacerbation of chronic obstructive pulmonary disease, and asked to select diagnostic tests as well as 1 of 6 antibiotics. Two antibiotics were expensive (ciprolloxacin and cefaclor; average price $Can52.23). and 4 inexpensive [amoxicillin. couimoxazole (trimethoprim/sulfamethoxazole), erythromycin and tetracycline; average price $Can2.80]. Neither expensive drug is considered first line therapy for the condition described. Questionnaires differed in the presence or absence of drug benefit coverage and price information. The response rate was 71 %. With third party cost coverage and prices shown, 18% of respondents selected an expensive antibiotic. This increased to 38% when the prices were omitted [odds ratio 2.72; 95% confidence interval (CI) 1.61, 4.60; p < 0.001], and decreased to 8% when the patient was said to have no drug benefits coverage (odds ratio 0.40; 95% CI 0.19, 0.84; p < 0.01). On a control questionnaire in which neither cost coverage nor prices were specified. and in which respondents were asked to indicate the most appropriate antibiotic, 37% selected an expensive drug (relative to the version giving both prices and cost coverage: odds ratio 2.70; 95% CI 1.62, 4.53; P < 0.001). We conclude that inappropriate selection of expensive antibiotics is increased when the patient has full drug benefit coverage but reduced when physicians are reminded of drug prices. These results support assessment of a price-oriented educational intervention in an effort to reduce inappropriately expensive prescribing.

Study Objectives : To assess specialists' adaptation to long waiting lists for coronary revascularization, and their acceptance of a formal queue-ordering schema proposed by an expert panel . Design : Mail survey of practitioners in referral centers using 49 hypothetical case scenarios. Scenarios were rated for maximum acceptable delay prior to coronary surgery, on a scale with seven interventional time frames graded from emergency to three to six months' permissible delay. The survey included the proposed schema and rating system; respondents were invited to differ as they saw fit . Hypothetical Patients : Assumed uniformly to be middle aged with typical angina, but clinical factors varied , eg , severity and stability of angina, response to medical therapy, coronary anatomy, and noninvasive test results . Physician Subjects : There were 122 respondents, for a 60 percent response rate, including a majority of cardiac surgeons and invasive cardiologists on staff in Ontario teaching hospitals . Measurements and Results : Fifty-seven percent rated some scenarios for acceptable waiting times of three to six months; another 39 percent rated their least urgent scenarios to wait six weeks to three months. Interpractitioner agreement was high: for 48/49 scenarios, at least 75 percent of urgency ratings fell within two contiguous points on the scale. Symptom status was the dominant determinant of waiting time, with mean maximum acceptable wait of 74 days for patients with mild-moderate stable angina but three days for those receiving parenteral nitroglycerine (p . Conclusions : Specialist practitioners in Ontario have adapted to waiting lists for coronary artery bypass surgery/percutaneous transluminal coronary angioplasty, and assess the priority of hypothetical patients in similar ways and in reasonable accord with formal queue-ordering criteria. This behavior may help mitigate the impact of resource constraints, allowing delay of services for those with less acute need—a potential contrast to delayed access in America based on low income or lack of insurance .

A panel of 16 cardiologists and cardiac surgeons rated 438 case scenarios for the maximum acceptable delay prior to revascularization, using a scale with seven interventional time frames and two nodes for designating dubious or inappropriate cases. If consensus was defined as agreement by 12 or more panelists, only 1.4 percent of the case scenarios showed consensus on a single rating. Dividing the scale into three broad clinical categories (revascularize promptly, place on a waiting list, or no intervention), 11.4 percent of scenarios showed all 16 panelists agreeing on a single category, rising to 59.4 percent of scenarios if agreement by 12 panelists was accepted as a consensus. The mean difference between the panelists' highest and lowest urgency ratings yielded waiting time differences of two weeks for scenarios of very unstable angina, and more than three months for those with stable angina. However, in a regression model, individual panelist factors on average had less effect than clinical features such as severity and stability of angina, or stenosis of major coronary arteries. These findings strongly support the need for consensus criteria to ensure that triage practices are consistent and fair, and also suggest that widespread adoption of a standardized approach to revascularization priorities may be feasible.

The Toronto experience suggests that there may be several general lessons for academic health sciences complexes to learn from the Olivieri/Apotex affair (OAA) regarding the ethics, independence, and integrity of clinical research sponsored by for profit enterprises. From a local perspective, the OAA occurred when there already was a focus on the complex and changing relationships among the University of Toronto, its medical school, the fully affiliated teaching hospitals, and off campus faculty because of intertwined interests and responsibilities. The OAA became a catalyst that accelerated various systemic reforms, particularly concerning academic/industry relations. In this article, the evolving governance framework for the Toronto academic health sciences complex is reviewed and these policy and process reforms discussed. These reforms have created collaborative activity among research ethics boards and contract research offices of the partner institutions, and allowed the joint university/hospital ethics centre to play a role in governance and policy, while respecting the missions and mandates of the involved institutions. Although few of the policies are dramatically innovative, what is arguably novel is the elaboration of an overarching governance framework that aims to move ethics to a central focus in the academic complex. Time alone will tell how sustainable and effective these changes are.

Background:Patients with Parkinsonism have a progressive disorder requiring substantial expertise to manage effectively.Methods:Over a six-year period we evaluated physician utilization and related costs for a large, unselected cohort of 15,304 Parkinsonian patients from the general population, comparing them to 30,608 age- and sex-matched controls within a universal health care system in Ontario, Canada.Results:On average, 45% of Parkinsonian patients saw neurologists annually. The cumulative rate of at least one neurological consultation was only 59.5% over the six years. Patients aged Conclusions:Parkinsonian patients had increased likelihood of utilizing neurologists, primary care physicians and internists compared to controls; related costs of physicians’ services were higher. Further research is necessary to evaluate differences in outcomes and costs between neurologists and other physician service providers.

Background: PD was associated with increased mortality before levodopa therapy became available. There have been conflicting reports of PD mortality in the modern era. Objective: To assess current mortality rates in a large unselected population receiving treatment for parkinsonism (PKM) followed for up to 6 years. Methods: Cases were identified using linked administrative databases, including physician service and prescription drug claims, generated in Ontario’s universal health insurance system. Control subjects were identified from the provincial registry of citizens and age and sex matched to cases. Comparative mortality was evaluated over the 6-year period of the study (1993/94 to 1998/99). The sensitivity of the findings was tested with differing case definitions. Results: In 1993, 15,304 patients with PKM were identified and were age and sex matched to 30,608 control subjects (1:2 ratio). Over the study period, 50.8% (7,779) of the cases with PKM died compared with 29.1% (8,899) of the control subjects. The cases with PKM had an overall mortality odds ratio of 2.5 (95% CI: 2.4, 2.6) compared with the control group. Results were consistent whether cases were defined by physician diagnosis, use of anti-PD drugs, or both criteria. Conclusion: Despite modern drug therapy, PKM continues to confer a sharply increased mortality on unselected patients followed for several years.

Diabetes is a recognized risk factor for the development of cardiac disease, but its importance as a prognostic factor among patients with known cardiovascular disease is less clear. We evaluated survival in patients with and without diabetes who underwent cardiac catheterization for presumed coronary artery disease.We analyzed data from a prospective cohort study that captures detailed clinical information and longitudinal outcomes for all patients who undergo cardiac catheterization in Alberta, Canada. We studied 11,468 patients, 1959 (17%) of whom had diabetes. Logistic regression was used to model predictors of 1-year mortality, and proportional hazards analysis was used to model predictors of survival up to 3 years after cardiac catheterization.One-year mortality was 7.6% for patients with diabetes versus 4.1% for those without diabetes (odds ratio = 1.9, 95% confidence interval [CI]: 1.6 to 2.3). After adjusting for other characteristics of the patients, including comorbid conditions, previous cardiac history, coronary anatomy, and renal function, the odds ratio for 1-year mortality was 1.1 (95% CI: 0.8 to 1.3). Similarly, the adjusted hazard ratio for longer term mortality was 1. 2 (95% CI: 1.0 to 1.4, mean follow-up of 702 days).These results suggest that there is little or no independent association between diabetes and mortality for up to 3 years after cardiac catheterization. Estimates of short- to intermediate-term prognosis for diabetic patients with coronary artery disease should be based on the presence of other prognostic factors associated with diabetes.

This series provides clinicians with strategies and tools to interpret and integrate evidence from published research in their care of patients. The 2 key principles for applying all the articles in this series to patient care relate to the value-laden nature of clinical decisions and to the hierarchy of evidence postulated by evidence-based medicine. Clinicians need to be able to distinguish high from low quality in primary studies, systematic reviews, practice guidelines, and other integrative research focused on management recommendations. An evidence-based practitioner must also understand the patient's circumstances or predicament; identify knowledge gaps and frame questions to fill those gaps; conduct an efficient literature search; critically appraise the research evidence; and apply that evidence to patient care. However, treatment judgments often reflect clinician or societal values concerning whether intervention benefits are worth the cost. Many unanswered questions concerning how to elicit preferences and how to incorporate them in clinical encounters constitute an enormously challenging frontier for evidence-based medicine. Time limitation remains the biggest obstacle to evidence-based practice but clinicians should seek evidence from as high in the appropriate hierarchy of evidence as possible, and every clinical decision should be geared toward the particular circumstances of the patient.

Clinicians rely on knowledge about the clinical manifestations of disease to make clinical diagnoses. Before using research on the frequency of clinical features found in patients with a disease, clinicians should appraise the evidence for its validity, results, and applicability. For validity, 4 issues are important-how the diagnoses were verified, how the study sample relates to all patients with the disease, how the clinical findings were sought, and how the clinical findings were characterized. Ideally, investigators will verify the presence of disease in study patients using credible criteria that are independent of the clinical manifestations under study. Also, ideally the study patients will represent the full spectrum of the disease, undergo a thorough and consistent search for clinical findings, and these findings will be well characterized in nature and timing. The main results of these studies are expressed as the number and percentages of patients with each manifestation. Confidence intervals can describe the precision of these frequencies. Most clinical findings occur with only intermediate frequency, and since these frequencies are equivalent to diagnostic sensitivities, this means that the absence of a single finding is rarely powerful enough to exclude the disease. Before acting on the evidence, clinicians should consider whether it applies to their own patients and whether it has been superseded by new developments. Detailed knowledge of the clinical manifestations of disease should increase clinicians' ability to raise diagnostic hypotheses, select differential diagnoses, and verify final diagnoses. JAMA. 2000;284:869-875

Clinical experience provides clinicians with an intuitive sense of which findings on history, physical examination, and investigation are critical in making an accurate diagnosis, or an accurate assessment of a patient's fate. A clinical decision rule (CDR) is a clinical tool that quantifies the individual contributions that various components of the history, physical examination, and basic laboratory results make toward the diagnosis, prognosis, or likely response to treatment in a patient. Clinical decision rules attempt to formally test, simplify, and increase the accuracy of clinicians' diagnostic and prognostic assessments. Existing CDRs guide clinicians, establish pretest probability, provide screening tests for common problems, and estimate risk. Three steps are involved in the development and testing of a CDR: creation of the rule, testing or validating the rule, and assessing the impact of the rule on clinical behavior. Clinicians evaluating CDRs for possible clinical use should assess the following components: the method of derivation; the validation of the CDR to ensure that its repeated use leads to the same results; and its predictive power. We consider CDRs that have been validated in a new clinical setting to be level 1 CDRs and most appropriate for implementation. Level 1 CDRs have the potential to inform clinical judgment, to change clinical behavior, and to reduce unnecessary costs, while maintaining quality of care and patient satisfaction. JAMA. 2000;284:79-84

Universal health care systems seek to ensure access to care on the basis of need rather than income and to improve the health status of all citizens. We examined the performance of the Canadian health system with respect to these goals in the province of Ontario by assessing the effects of neighborhood income on access to invasive cardiac procedures and on mortality one year after acute myocardial infarction.We linked claims for payment for physicians' services, hospital-discharge abstracts, and vital-status data for all patients with acute myocardial infarction who were admitted to hospitals in Ontario between April 1994 and March 1997. Patients' income levels were imputed from the median incomes of their residential neighborhoods as determined in Canada's 1996 census. We determined rates of use and waiting times for coronary angiography and revascularization procedures after the index admission for acute myocardial infarction and determined death rates at one year. In multivariate analyses, we controlled for the patient's age, sex, and severity of disease; the specialty of the attending physician; the volume of cases, teaching status, and on-site facilities for cardiac procedures at the admitting hospital; and the geographic proximity of the admitting hospital to tertiary care centers.The study cohort consisted of 51,591 patients. With respect to coronary angiography, increases in neighborhood income from the lowest to the highest quintile were associated with a 23 percent increase in rates of use and a 45 percent decrease in waiting times. There was a strong inverse relation between income and mortality at one year (P0.001). Each $10,000 increase in the neighborhood median income was associated with a 10 percent reduction in the risk of death within one year (adjusted hazard ratio, 0.90; 95 percent confidence interval, 0.86 to 0.94).In the province of Ontario, despite Canada's universal health care system, socioeconomic status had pronounced effects on access to specialized cardiac services as well as on mortality one year after acute myocardial infarction.

Driven by fiscal pressures in the 1990s, Canada's provincial Medicare systems cut inpatient care, expanded community services, and consolidated hospitals under regional authorities in nine of ten provinces. Public confidence has been badly shaken by the transition. No province has successfully integrated services across the continuum of care. Home care and prescription drug coverage vary from province to province. Efforts to reform physician payment have stalled, and capacity to measure and manage the quality of care is generally underdeveloped. Thus, for the next few years, policymakers must stabilize the acute care sector, while cautiously pursuing an agenda of piece-meal reforms.

Laboratory evidence supports the use of adenosine-supplemented cardioplegia. An initial phase 1 dose-ranging clinical evaluation demonstrated that an adenosine concentration of 15 mumol/L could be safely administered with warm blood cardioplegia and suggested that phase 2 studies were warranted.Two separate double-blind, randomized, placebo-controlled trials were performed in patients undergoing primary, isolated, nonemergent coronary artery bypass graft surgery. Patients were randomized to receive adenosine 15 mumol/L versus placebo in the first study (n = 200) and adenosine 50 or 100 mumol/L versus placebo in the second study (n = 128). Adenosine was infused with both initial and final doses of warm antegrade blood cardioplegia. The data from the 2 trials were combined using the methods of Mantel and Haenszel, and the results of the meta-analysis are presented as the relative risk with their associated 95% confidence intervals (CI). The different study groups were comparable with respect to all preoperative clinical characteristics, angiographic findings, and intraoperative variables. In both trials 1 and 2, no differences were found between groups in the incidence of the individual primary or secondary outcomes. Similarly, when both studies were combined, there was no significant evidence of any consistent treatment benefit (primary: death: relative risk [RR] = 1.02, 95% CI = 0.06, 16.6; myocardial infarction by CK-MB: RR = 0.84, CI = 0.54, 1.31; low output syndrome: RR = 1.38, CI = 0.29, 6.42; any of the above: RR = 0.98, CI = 0.78, 1.25; secondary: Q-wave myocardial infarction: RR = 1.30, CI = 0.41, 4.13; myocardial infarction by troponin T: RR = 0.7, CI = 0.40, 1.21; inotrope requirement: RR = 0.9, CI = 0.46, 1.79; intra-aortic balloon pump requirement: RR = 0.6, CI = 0.07, 4.81; P0.20).Despite promising experimental data, adenosine supplementation of warm blood cardioplegia did not demonstrate any statistically significant benefit in patients undergoing elective coronary artery bypass graft surgery. Although sample sizes were relatively small, based on our interim analyses, it is unlikely that increased patient enrollment would reveal any substantive clinical differences between groups.

The public health insurance system in Canada is predicated on equal access to care for persons in need.To determine the views and experiences of Ontario physicians and hospital administrators in providing patients with preferential access to specialized cardiovascular care on the basis of nonclinical factors.Survey with self-administered questionnaire.Ontario, Canada.All Ontario cardiologists (n = 268), cardiac surgeons (n = 68), and hospital chief executives (n = 218) and random samples of internists (n = 300) and family physicians (n = 300).Elicited responses (yes or no) to questions on whether and why preferential access occurred and whether the respondents had been personally involved in such a situation.After undeliverable surveys and respondents no longer involved with acute care were excluded, the eligible response rate was 71.3% (788 of 1105 respondents). More than 80% of physicians and 53% of hospital chief executives had been personally involved in managing a patient who had received preferential access on the basis of factors other than medical need. Patients deemed most likely to receive such treatment were those with personal ties to the treating physicians (93% [95% CI, 91% to 95%]), high-profile public figures (85% [CI, 82% to 87%]), and politicians (83% [CI, 80% to 86%]). Physicians were significantly more likely than chief executives to indicate that hospital board members (81% and 68%; P0.001) and donors to hospital foundations (63% and 42%; P0.001) would receive preferential access. Most respondents indicated that preferential access was more likely to be provided if patients or families were well informed, aggressive, or potentially litigious. The survey did not permit estimation of the frequency of episodes of preferential access.Although equality of access is a cornerstone principle of Canada's universal health care system, some access to specialized cardiovascular services occurs preferentially on the basis of factors other than clinical need. The actual magnitude and consequences of this phenomenon remain unknown.

We assessed the use and effects of acute intravenous and later oral atenolol treatment in a prospectively planned post hoc analysis of the GUSTO-I dataset.Early intravenous beta blockade is generally recommended after myocardial infarction, especially for patients with tachycardia and/or hypertension and those without heart failure.Besides one of four thrombolytic strategies, patients without hypotension, bradycardia or signs of heart failure were to receive atenolol 5 mg intravenously as soon as possible, another 5 mg intravenously 10 min later and 50 to 100 mg orally daily during hospitalization. We compared the 30-day mortality of patients given no atenolol (n=10,073), any atenolol (n=30,771), any intravenous atenolol (n=18,200), only oral atenolol (n=12,545) and both intravenous and oral drug (n=16,406), after controlling for baseline differences and for early deaths (before oral atenolol could be given).Patients given any atenolol had a lower baseline risk than those not given atenolol. Adjusted 30-day mortality was significantly lower in atenolol-treated patients, but patients treated with intravenous and oral atenolol treatment vs. oral treatment alone were more likely to die (odds ratio, 1.3; 95% confidence interval, 1.0 to 1.5; p=0.02). Subgroups had similar rates of stroke, intracranial hemorrhage and reinfarction, but intravenous atenolol use was associated with more heart failure, shock, recurrent ischemia and pacemaker use than oral atenolol use.Although atenolol appears to improve outcomes after thrombolysis for myocardial infarction, early intravenous atenolol seems of limited value. The best approach for most patients may be to begin oral atenolol once stable.

In this study, we assessed maternal-fetal outcomes in untreated patients with increasing carbohydrate intolerance not meeting the current criteria for the diagnosis of gestational diabetes mellitus (GDM), examined the relationship between birth weight and mode of delivery among women with untreated borderline GDM, treated overt GDM, and normoglycemia, and established more efficient screening strategies for detection of GDM. This was a prospective analytic cohort study in which nondiabetic women agedor = 24 years were eligible for enrollment. A 50-g glucose challenge test (GCT) and a 100-g oral glucose tolerance test (OGTT) were administered at 26 and 28 weeks gestational age, respectively. Risk factors for unfavorable maternal-fetal outcomes were recorded. Time since the last meal prior to the screening test was recorded, as well. Caregivers and patients were blinded to glucose values except when test results met the National Diabetes Data Group criteria for GDM. Maternal and fetal outcomes, including the mode of the delivery, were recorded in the postpartum period. Of 4,274 patients screened, 3,836 (90%) continued to the diagnostic oral glucose tolerance test. GDM was seen in 145 women. Increasing carbohydrate intolerance in women without overt gestational diabetes was associated with a significantly increased incidence of cesarean section, preeclampsia, macrosomia, and need for phototherapy, as well as an increased length of maternal and neonatal hospital stay. Multivariate analysis showed that increasing carbohydrate intolerance remained an independent predictor for various unfavorable outcomes, but the strength of the associations was diminished. Compared with normoglycemic control subjects, the untreated borderline GDM group had increased rates of macrosomia (28.7 vs. 13.7%, P0.001) and cesarean delivery (29.6 vs. 20.2%, P = 0.03). Usual care of known GDM patients normalized birth weights, but the cesarean delivery rate was about 33%, whether macrosomia was present or absent. An increased risk of cesarean delivery among treated patients compared with normoglycemic control subjects persisted after adjustment for multiple maternal risk factors. As for the screening tests, time since the last meal had a marked effect on mean plasma glucose. Receiver operating characteristic curve analysis allowed the selection of the most efficient cut points for the GCT based on the time since the last meal. These cut points were 8.2, 7.9, and 8.3 mmol/l (1 mmol/l = 18.015 mg/dl) for elapsed postprandial time of2, 2-3, and3 h, respectively. With this change from the current threshold of 7.8 mmol/l, the number of patients with a positive screening test dropped from 18.5 to 13.7%. There was an increase in positive predictive value from 14.4 to 18.7%. The overall rate of patient misclassification fell from 18.0 to 13.1%. In conclusion, increasing maternal carbohydrate intolerance in pregnant women without GDM is associated with a graded increase in adverse maternal and fetal outcomes. Infant macrosomia is an important factor in high cesarean delivery rates for women with untreated borderline GDM. Although detection and treatment of GDM normalizes birth weights, rates of cesarean delivery remain inexplicably high. Recognition of GDM may lead to a lower threshold for surgical delivery. The efficiency of screening for GDM can be enhanced by adjusting the current GCT threshold of 7.8 mmol/l to new values related to time since the last meal before screening. Further analyses are underway to elucidate whether maternal risk factors can be used to achieve additional efficiency gains in screening.

BACKGROUND: Previous studies of hospital utilization have not taken into account the use of acute care beds for subacute care. The authors determined the proportion of patients who required acute, subacute and nonacute care on admission and during their hospital stay in general hospitals in Ontario. From this analysis, they identified areas where the efficiency of care delivery might be improved. METHODS: Ninety-eight of 189 acute care hospitals in Ontario, at 105 sites, participated in a review that used explicit criteria for rating acuity developed by Inter-Qual Inc., Marlborough, Mass. The records of 13,242 patients who were discharged over a 9-month period in 1995 after hospital care for 1 of 8 high-volume, high-variability diagnoses or procedures were randomly selected for review. Patients were categorized on the basis of the level of care (acute, subacute or nonacute) they required on admission and during subsequent days of hospital care. RESULTS: Of all admissions, 62.2% were acute, 19.7% subacute and 18.1% nonacute. The patients most likely to require acute care on admission were those with acute myocardial infarction (96.2% of 1826 patients) or cerebrovascular accident (84.0% of 1596 patients) and those admitted for elective surgery on the day of their procedure (73.4% of 3993 patients). However, 41.1% of patients awaiting hip or knee replacement were admitted the day before surgery so did not require acute care on admission. The proportion of patients who required acute care on admission and during the subsequent hospital stay declined with age; the proportion of patients needing nonacute care did not vary with age. After admission, acute care was needed on 27.5% of subsequent days, subacute care on 40.2% and nonacute care on 32.3%. The need for acute care on admission was a predictor of need for acute care during subsequent hospital stay among patients with medical conditions. The proportion of patients requiring subacute care during the subsequent hospital stay increased with age, decreased with the number of inpatient beds in each hospital and was highest among patients with congestive heart failure, chronic obstructive pulmonary disease and pneumonia. INTERPRETATION: In 1995, inpatients requiring subacute care accounted for a substantial proportion of nonacute care days in Ontario's general hospitals. These findings suggest a need to evaluate the efficiencies that might be achieved by introducing a subacute category of care into the Canadian health care system. Generally, efforts are needed to reduce the proportion of admissions for nonacute care and of in-hospital days for other than acute care.

To compare the abilities of artificial neural network and logistic regression models to predict the risk of in-hospital mortality after coronary artery bypass graft (CABG) surgery.Neural network and logistic regression models were developed using a training set of 4,782 patients undergoing CABG surgery in Ontario, Canada, in 1991, and they were validated in two test sets of 5,309 and 5,517 patients having CABG surgery in 1992 and 1993, respectively.The probabilities predicted from a fully trained neural network were similar to those of a "saturated" regression model, with both models detecting all possible interactions in the training set and validating poorly in the two test sets. A second neural network was developed by cross-validating a network against a new set of data and terminating network training early to create a more generalizable model. A simple "main effects" regression model without any interaction terms was also developed. Both of these models validated well, with areas under the receiver operating characteristic curves of 0.78 and 0.77 (p0.10) in the 1993 test set. The predictions from the two models were very highly correlated (r=0.95).Artificial neural networks and logistic regression models learn similar relationships between patient characteristics and mortality after CABG surgery.

We assessed patients on the waiting lists of a purposive sample of orthopaedic surgeons in Ontario, Canada, to determine patients' attitudes towards time waiting for hip or knee replacement. We focused on 148 patients who did not have a definite operative date, obtaining complete information on 124 (84%). Symptom severity was assessed with the Western Ontario/McMaster Osteoarthritis Index and a disease-specific standard gamble was used to elicit patients' overall utility for their arthritic state. Next, in a trade-off task, patients considered a hypothetical choice between a 1-month wait for a surgeon who could provide a 2% risk of post-operative mortality, or a 6-month wait for joint replacement with a 1% risk of post-operative mortality. Waiting times were then shifted systematically until the patient abandoned his/her initial choice, generating a conditional maximal acceptable wait time. Patients were divided in their attitudes, with 57% initially choosing a 6-month wait with a 1% mortality risk. The overall distribution of conditional maximum acceptable wait time scores ranged from 1 to 26 months, with a median of 7 months. Utility values were independently but weakly associated with patients' tolerance of waiting times (adjusted R-square = 0.059, P = 0.004). After splitting the sample along the median into subgroups with a relatively 'low' and 'high' tolerance for waiting, the subgroup with the apparently lower tolerance for waiting reported lower utility scores (z = 2.951; P = 0.004) and shorter times since their surgeon first advised them of the need for surgery (z = 3.014; P = 0.003). These results suggest that, in the establishment and monitoring of a queue management system for quality-of-life-enhancing surgery, patients' own perceptions of their overall symptomatic burden and ability to tolerate delayed relief should be considered along with information derived from clinical judgements and pre-weighted health status instruments.

Objectives—To assess death rates among patients waiting for cardiac valve surgery or isolated coronary artery bypass surgery (CABG), and to determine independent risk factors for death while waiting for isolated CABG. Design—Prospective cohort analysis based on an inclusive registry. Setting—Nine cardiac surgical units in Ontario, Canada. Patients—29 293 consecutive patients scheduled for cardiac surgery between October 1991 and June 1995. Main outcome measures—Death rates while waiting for surgery were determined among patients scheduled for isolated CABG, isolated valve surgery, or combined procedures. Predictors of death among patients with isolated CABG were determined from multivariate analysis. Results—There were 141 deaths (0.48%) among 29 293 patients. Adjusting for age, sex, and waiting time, patients waiting for valve surgery had a significantly increased risk of death compared with patients waiting for CABG alone (adjusted odds ratio 1.88, 95% confidence interval (CI) 1.23 to 2.88, p = 0.004). Results were similar for patients waiting for combined valve and CABG procedures compared with those who were waiting for isolated CABG. Independent risk factors for death while waiting for isolated CABG included: impaired left ventricular function (odds ratio 2.47, 95% CI 1.59 to 3.84, p

The usual approach to detecting gestational diabetes mellitus is to screen all pregnant women by measuring their plasma glucose after a 50-g oral glucose load at 24 to 28 weeks' gestation. Women are referred for an oral glucose-tolerance test if the plasma glucose concentration one hour later isor = 140 mg per deciliter (7.8 mmol per liter). We hypothesized that the efficiency of screening could be enhanced by considering women's risks of gestational diabetes on the basis of their clinical characteristics.We studied 3131 pregnant women who underwent both the screening and the diagnostic tests. We randomly selected data on half the women and used them to derive new screening strategies. We categorized each woman's risk of gestational diabetes mellitus on the basis of her age, body-mass index before pregnancy, and race. We developed strategies that entailed no screening for low-risk women, usual care for intermediate-risk women, and universal screening with lower thresholds -- plasma glucose values of 130 mg per deciliter (7.2 mmol per liter) or 128 mg per deciliter (7.1 mmol per liter) -- for high-risk women. The strategies were validated with data on the other half of the women.The new strategies allowed a 34.6 percent reduction in the number of screening tests performed (95 percent confidence interval, 32.3 to 37.0) and detected 81.2 to 82.6 percent of the women with gestational diabetes as compared with the 78.3 percent detected through usual care. The percentage of false positive screening tests was significantly reduced, from 17.9 percent with usual care to 16.0 per cent (P=0.02) or 15.4 percent (P0.001) with the new strategies, depending on the threshold values for high-risk women.Consideration of women's clinical characteristics allows efficient selective screening for gestational diabetes.

We sought to determine whether more comprehensive risk-adjustment models have a significant impact on hospital risk-adjusted mortality rates after coronary artery bypass graft surgery (CABG) in Ontario, Canada.The Working Group Panel on the Collaborative CABG Database Project has categorized 44 clinical variables into 7 core, 13 level 1 and 24 level 2 variables, to reflect their relative importance in determining short-term mortality after CABG.Using clinical data for all 5,517 patients undergoing isolated CABG in Ontario in 1993, we developed 12 increasingly comprehensive risk-adjustment models using logistic regression analysis of 6 of the Panel's core variables and 6 of the Panel's level 1 variables. We studied how the risk-adjusted mortality rates of the nine cardiac surgery hospitals in Ontario changed as more variables were included in these models.Incorporating six of the core variables in a risk-adjustment model led to a model with an area under the receiver operating characteristic (ROC) curve of 0.77. The ROC curve area slightly improved to 0.79 with the inclusion of six additional level 1 variables (p = 0.063). Hospital risk-adjusted mortality rates and relative rankings stabilized after adjusting for six core variables. Adding an additional six level 1 variables to a risk-adjustment model had minimal impact on overall results.A small number of core variables appear to be sufficient for fairly comparing risk-adjusted mortality rates after CABG across hospitals in Ontario. For efficient interprovider comparisons, risk-adjustment models for CABG could be simplified so that only essential variables are included in these models.

PURPOSE Along with evidence, clinical policies must take patients' values into account. Particularly where evidence is limited and where assumptions of utility-maximizing behavior may not be valid, new methods such as trade-off techniques (TOTs), which allow elicitation of patients' treatment alternatives, might be useful in policy formulation. We used TOTs to assess breast cancer patients' attitudes toward two clinical policies designed to ration adjuvant postlumpectomy breast radiation therapy. METHODS Cross-sectional interviews were performed in a tertiary cancer center. A total of 102 patients were presented with information about the side effects and benefits associated with two hypothetical decisions: (1) willingness to receive treatment elsewhere to shorten the wait for radiation therapy, and (2) foregoing radiation therapy in the face of small marginal benefits. For each scenario, a TOT was used to identify the maximal acceptable wait time (MAWT) for therapy and the benefit threshold at which the patient would forego therapy. Associations of clinical and demographic factors with these decisions were determined by regression analysis. RESULTS Patients would be willing to wait, on average, 7 weeks before wanting to leave their city for radiation therapy, less than the 13-week delay our patients actually faced. Older patients were less willing to wait (P = .013); 46% of patients would not give up radiation therapy, even in the face of no stated benefit. Willingness to give up radiation therapy was predicted by willingness to accept delay (odds ratio [OR], 1.84; 95% confidence interval [CI], 1.05 to 3.37) and being employed (OR, 2.61; 95% CI, 1.08 to 6.54). Patients with larger tumors were less willing to give up radiation therapy (OR, 0.57; 95% CI, 0.31 to 0.97). CONCLUSION Even in difficult decisions such as rationing postlumpectomy breast cancer radiation therapy, TOTs can inform policy formulation by indicating the distributions of patients' preferences.

This week's BMJ contains a pot-pourri of materials that deal with the research methodology of meta-analysis. Meta-analysis in clinical research is based on simple principles: systematically searching out, and, when possible, quantitatively combining the results of all studies that have addressed a similar research question. Given the information explosion in clinical research, the logic of basing research reviews on systematic searching and careful quantitative compilation of study results is incontrovertible. However, one aspect of meta-analysis as applied to randomised trials has always been controversial1 2 –combining data from multiple studies into single estimates of treatment effect. In theory, aggregation of data from multiple trials should enhance the precision and accuracy of any pooled result. But combining data requires a leap of faith: it presumes that the differences among studies are primarily due to chance. In fact, differences in the direction or size of treatment effects may be caused by other factors, including subtle differences in treatments, populations, outcome measures, study design, and study quality.3 Thus meta-analyses may generate misleading results by ignoring meaningful heterogeneity among studies, entrenching the biases in individual studies, and introducing further biases through the process of finding studies and selecting results to be pooled. Our understanding of these limits of meta-analysis has arisen partly because a generation of investigators has stepped back from the unthinking pooling of data and begun researching clinical research itself. Those interested in the science of systematic reviews focus on trials as the unit of analysis; and along the way they have usefully shifted the goalposts for reporting on clinical research. Among the surprising challenges in any systematic review is finding all the studies that have addressed the question(s) of interest. Many studies have documented publication bias favouring clinical trials that show a significant treatment effect. Stern and Simes extend …

To pilot-test a simple checklist designed to improve coding of acute myocardial infarction (AMI) in hospital discharge abstracts.Health records technologists review hospital charts to code discharge diagnoses according to the International Classification of Diseases, 9th revision (ICD-9). Many studies have suggested that there is a high false positive rate in coding AMI, ie, ICD-9 410, on hospital discharge abstracts.The checklist required either at least two of suggestive symptoms, diagnostic electrocardiographic changes, or diagnostic rise in serum cardiac enzymes; or confirmation by autopsy. First case of use was confirmed-typical time to complete the checklist was 3 to 4 mins. Then 16 Ontario community hospitals were recruited to apply the checklist on a blinded basis to 1000 randomly drawn in-patient records-10% were audited for another study to confirm AMI; and 90% were originally coded with 'most responsible diagnosis' (MRD) of AMI, other cardiovascular diagnoses and various noncardiac conditions. Percentage agreement (95% CI) between the checklist and the confirmed or coded diagnosis was analyzed; coding of AMI as a secondary diagnosis was examined in further analyses.One hospital withdrew for logistical reasons; the final useable sample from 15 hospitals was 943 records. The checklist correctly identified 100% of AMIs independently confirmed for another study; usual coding identified 89.7% of cases (70 of 78; 95% CI 80.8 to 95.5). For cases not confirmed, but where the physician had nonetheless diagnosed AMI, six of 11 charts were miscoded as AMI in hospital records; none were miscoded by the checklist. For records with AMI as MRD, 11.6% (44 of 380; 95% CI 8.5 to 15.2) were classified as false positives by the checklist. Where an AMI was coded as a secondary diagnosis, 52.9% (36 of 68; 95% CI 40.5 to 65.2) met the checklist criteria for AMI. Finally, among records where the MRD was other than AMI, 6.8% (38 of 563; 95% CI 4.8 to 9.2) met checklist criteria for AMI during admission, but 94.7% had an ICD-9410 code as a secondary diagnosis.A simple checklist can be very easily applied, has extremely high sensitivity for confirming the presence of AMI, and identifies a clinically significant proportion of charts with false positive codes for AMI. Conversely, these findings support the high sensitivity (low false negative rates) of conventional coding practices for AMI in Canadian hospital records, be it as a primary or secondary diagnosis (eg, 95% detection rate). Usual coding, combined with the checklist for tentative ICD-9 410 diagnoses, would improve the accuracy of Canadian hospital records.

To establish whether clinically significant aortic and mitral valvular regurgitation can be excluded in adult patients undergoing transthoracic echocardiography without using colour flow imaging.Sunnybrook Health Science Centre, a tertiary referral centre with full cardiovascular services affiliated with the University of Toronto, Toronto, Ontario.Logistic regression models were developed from a retrospective review of 14,051 unselected consecutive echocardiograms from 1991 through 1994. The dependent variable was more than mild aortic or mitral valvular regurgitation. Independent variables included age, sex and various functional and structural measures obtained during routine two-dimensional echocardiography. The negative predictive values and sensitivity of the models were estimated.The number of patients correctly classified by these models, as well as the proportion for whom the colour flow imaging did not add to the baseline echocardiogram, was determined. Nonparametric bootsrapping was used to obtain confidence intervals for these statistics.Ten models were developed, with negative predictive values ranging from 96.2% to 100%. Incorporation of such decision aids into the software of echocardiographic machinery would help echocardiographers to rule out significant aortic or mitral regurgitant lesions. In practices where colour flow imaging is routinely employed, 40% fewer procedures could be performed.Models based on simple demographic and two-dimensional echocardiographic variables can reliably exclude significant valvular regurgitation and could potentially reduce the volumes and costs of colour flow imaging. Given the widespread diffusion of colour Doppler imaging, the models may also be helpful to avoid misinterpretation of flow imaging results, by defining subgroups in whom the prior probability of significant aortic or mitral regurgitation is extremely low.

To compare the types of patients selected for coronary angiography (CA) and coronary artery bypass graft (CABG) surgery, and the appropriateness of the procedures performed on these patients in a random sample of cases in British Columbia and Ontario.Retrospective randomized medical record review.All hospitals performing CA and/or CABG in British Columbia and Ontario in fiscal year 1989/90.For CA, 395 randomly selected patients in Ontario and 139 randomly selected patients in British Columbia; for CABG, 431 randomly selected patients in Ontario and 125 randomly selected patients in British Columbia.Case selection was measured in terms of the demographic and clinical characteristics of patients undergoing the procedures. Appropriateness was measured by comparing the clinical characteristics of patients undergoing the procedures with explicit criteria established by a panel of Canadian physicians. The yield from CA was measured as the proportion of patients who were found to have insignificant anatomical disease.Analysis of patients selected for CA showed that sample patients from Ontario were less likely than those from British Columbia to be female (25% versus 37%, respectively, P = 0.012) and less likely to have undergone a previous revascularization (12% versus 24%, respectively, P = 0.005). The distribution of main indications for CA differed between the two provinces (P = 0.002), with Ontario patients more likely to have chronic stable angina (45% versus 24%) and less likely to have unstable angina (16% versus 26%). For CABG, sample patients from Ontario were less likely to be 65 years of age or older (32% versus 45%, P = 0.016) and more likely to have an ejection fraction less than 35% (14% versus 5%, P = 0.006). The distribution of the main indications for CABG differed (P0.001), with Ontario patients more likely to have chronic stable angina (68% versus 38%) and less likely to have unstable angina (20% versus 43%). There was no statistically significant difference in CA cases rated as inappropriate (8.4% in Ontario versus 10.8% in British Columbia, P = 0.396) or CABG cases rated as inappropriate (3.9% in Ontario versus 2.4% in British Columbia, P = 0.393). There were no statistically significant differences in the proportion of CA that yielded insignificant anatomical disease (17.5% in Ontario versus 18.4% in British Columbia, P = 0.355).There were differences between Ontario and British Columbia in the demographic and clinical characteristics of patients selected for CA and CABG. This may indicate differences in the referral process in the two provinces. Despite these differences the rates of inappropriate procedures and the yield from CA were similar.

The objectives of this study were to assess the impact of major joint replacements in reducing pain and disability and to describe the burden of pain and disability that could be avoided by ordering the queues with respect to severity of disease. A secondary goal was to compare the uses of a general health status measure, the Short Form Health Survey (SF-36), and a disease-specific measure, the Western Ontario McMaster Osteoarthritis Index (WOMAC), for accomplishing the objectives. The results are based on interviews with 209 patients before and after they had surgery. Only 15.9% of the patients had surgery within 3 months' waiting time, 19.2% waited 4-6 months, 30.7% waited 7-9 months, and the remaining 34.1% waited a year or more. The waiting times were unrelated to the severity of pain or disability reported in the initial interview. Following surgery, there were large reductions in the WOMAC scores for pain, stiffness and difficulty in functioning. The SF-36 showed substantial improvements in relief from pain and in physical functioning, and reductions in role limitation due to physical problems, but not for scores related to mental health. The WOMAC scores were more responsive to the benefits of surgery than the SF-36 scores. Queuing systems keyed on burden of symptoms could reduce the burden of pain and disability suffered by patients awaiting surgery. The improvements from hip and knee replacements suggest that equitable access for these procedures should be a priority in Ontario.