A S Detsky

University of Toronto, Toronto, Ontario, Canada

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Publications (90)752.29 Total impact

  • Article: Randomized, controlled trial of an interactive videodisc decision aid for patients with ischemic heart disease.
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    ABSTRACT: To determine the effect of the Ischemic Heart Disease Shared Decision-Making Program (IHD SDP) an interactive videodisc designed to assist patients in the decision-making process involving treatment choices for ischemic heart disease, on patient decision-making. Randomized, controlled trial. The Toronto Hospital, University of Toronto, Toronto, Ontario, Canada. Two hundred forty ambulatory patients with The primary outcome was patient satisfaction with the decision-making process. This was measured using the 12-item Decision-Making Process Questionnaire that was developed and validated in a randomized trial of the benign prostatic hyperplasia SDP. Secondary outcomes included patient knowledge (measured using 20 questions about knowledge deemed necessary for an informed treatment decision), treatment decision, patient-angiographer agreement on decision, and general health scores. Outcomes were measured at the time of treatment decision and/or at 6 months follow-up. Shared decision-making program scores were similar for the intervention and control group (71% and 70%, respectively; 95% confidence interval [CI] for 1% difference, -3% to 7%). The intervention group had higher knowledge scores (75% vs 62%; 95% CI for 13% difference, 8% to 18%). The intervention group chose to pursue revascularization less often (58% vs 75% for the controls; 95% CI for 17% difference, 4% to 31%). At 6 months, 52% of the intervention group and 66% of the controls had undergone revascularization (95% CI for 14% difference, 0% to 28%). General health and angina scores were not different between the groups at 6 months. Exposure to the IHD SDP resulted in more patient-angiographer disagreement about treatment decisions. There was no significant difference in satisfaction with decision-making process scores between the IHD SDP and usual practice groups. The IHD SDP patients were more knowledgeable, underwent less revascularization (interventional therapies), and demonstrated increased patient decision-making autonomy without apparent impact on quality of life.
    Journal of General Internal Medicine 11/2000; 15(10):685-93. · 2.83 Impact Factor
  • Article: Charges for medical care at different hospitals.
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    ABSTRACT: The United States has a high proportion of people without health insurance (15%) and a low proportion of people without employment (5%), resulting in millions who lack insurance but have some ability to pay. We tested whether hospitals charge similar prices for well-specified elective services to individuals paying out-of-pocket for medical care. We surveyed the 2 largest general hospitals from every large city (population >500 000) in the United States and Canada. At each hospital we evaluated 5 diagnostic, 7 therapeutic, and 3 nonclinical services to determine the total charge to patients who pay directly. Overall, 66 hospitals were included (average, 758 beds; not-for-profit, 97% [n = 64]; teaching, 80% [n = 53]). The range in charges was substantial; for example, a screening mammogram was $40 at one hospital in Los Angeles, Calif, and $346 at one hospital in Quebec City. Charges for a screening mammogram were relatively stable between 1996 and 1997 (r=0.79; 95% confidence interval, 0.68-0.87) and unrelated to the hospital's location or charges for other services. The relative amount of variation in charges was similar for high-priced and low-priced services, similar for diagnostic and therapeutic services, and similar for the United States and Canada. Charges for the same hospital service vary substantially. Greater visibility might reduce some variation by bringing outliers into closer scrutiny. Patients seeking care and paying out-of-pocket could save financially by comparison shopping.
    Archives of Internal Medicine 05/2000; 160(10):1417-22. · 11.46 Impact Factor
  • Article: Biotechnology stock prices before public announcements: evidence of insider trading?
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    ABSTRACT: Unique financial challenges faced by biotechnology companies developing therapeutics have contributed to the creation of a highly sensitive market, where stock prices are capable of great fluctuation. The potential for significant financial reward and the nature of the scientific review process make this industry susceptible to illegal share trading on nonpublic information. We examined stock prices of biotechnology products before and after announcement of Phase III clinical trial and Food and Drug Administration (FDA) Advisory Panel results for indirect evidence of insider trading. Biotechnology stock prices were recorded for 98 products undergoing Phase III clinical trials and 49 products undergoing FDA Advisory Panel review between 1990 and 1998. Prices were recorded for 120 consecutive trading days before and after public announcement of these two events. We compared the average change in stock price of successful products ('winners') with unsuccessful products ('losers') before the public announcement of results for both critical events. The difference between average stock price change from 120 to 3 days before public announcement of results of Phase III clinical trial winners (+27%) and losers (-4%) was highly significant (P = 0.0007). A similar but non-significant difference was observed between the average stock price of winning (+27%) and losing products (+13%) before FDA Advisory Panel review announcements (P = 0.25). Our results provide indirect evidence that insider trading may be common in the biotechnology industry. Clinical investigators may wish to consider this issue before participating in any equity position in the biotechnology industry, especially if they are going to perform research for those companies.
    Journal of Investigative Medicine 04/2000; 48(2):118-24. · 1.96 Impact Factor
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    Article: Cost comparison of predictive genetic testing versus conventional clinical screening for familial adenomatous polyposis.
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    ABSTRACT: Mutations of the APC gene cause familial adenomatous polyposis (FAP), a hereditary colorectal cancer predisposition syndrome. To conduct a cost comparison analysis of predictive genetic testing versus conventional clinical screening for individuals at risk of inheriting FAP, using the perspective of a third party payer. All direct health care costs for both screening strategies were measured according to time and motion, and the expected costs evaluated using a decision analysis model. The baseline analysis predicted that screening a prototype FAP family would cost $4975/ pound3109 by molecular testing and $8031/ pound5019 by clinical screening strategy, when family members were monitored with the same frequency of clinical surveillance (every two to three years). Sensitivity analyses revealed that the genetic testing approach is cost saving for key variables including the kindred size, the age of screening onset, and the cost of mutation identification in a proband. However, if the APC mutation carriers were monitored at an increased (annual) frequency, the cost of the genetic screening strategy increased to $7483/ pound4677 and was especially sensitive to variability in age of onset of screening, family size, and cost of genetic testing of at risk relatives. In FAP kindreds, a predictive genetic testing strategy costs less than conventional clinical screening, provided that the frequency of surveillance is identical using either strategy. An additional significant benefit is the elimination of unnecessary colonic examinations for those family members found to be non-carriers.
    Gut 06/1999; 44(5):698-703. · 10.11 Impact Factor
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    Article: Direct costs of coronary artery bypass grafting in patients aged 65 years or more and those under age 65.
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    ABSTRACT: Over the past 20 years, there have been marked increases in rates of coronary artery bypass grafting (CABG) among older people in Canada. The objectives of this study were to accurately estimate the direct medical costs of CABG in older patients (age 65 years or more) and to compare CABG costs for this age group with those for patients less than 65 years of age. Direct medical costs were estimated from a sample of 205 older and 202 younger patients with triple-vessel or left main coronary artery disease who underwent isolated CABG at The Toronto Hospital, a tertiary care university-affiliated hospital, between Apr. 1, 1991, and Mar. 31, 1992. Costs are expressed in 1992 Canadian dollars from a third-party payer perspective. The mean costs of CABG in older and younger patients respectively were $16,500 and $15,600 for elective, uncomplicated cases, $23,200 and $19,200 for nonelective, uncomplicated cases, $29,200 and $20,300 for elective, complicated cases, and $33,600 and $23,700 for nonelective, complicated cases. Age remained a significant determinant of costs after adjustment for severity of heart disease and for comorbidity. Between 59% and 91% of the cost difference between older and younger patients was accounted for by higher intensive care unit and ward costs. CABG was more costly in older people, especially in complicated cases, even after an attempt to adjust for severity of disease and comorbidity. Future studies should attempt to identify modifiable factors that contribute to longer intensive care and ward stays for older patients.
    Canadian Medical Association Journal 04/1999; 160(6):805-11. · 8.22 Impact Factor
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    Article: Costs and cost-effectiveness of a universal, school-based hepatitis B vaccination program.
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    ABSTRACT: This study evaluated the costs and cost-effectiveness of a school-based grade 6 universal vaccination program against hepatitis B. We performed a descriptive cost study and cost-effectiveness analysis of British Columbia's vaccination program for 1994 and 1995. Since 1992, public health nurses have administered hepatitis B vaccine to grade 6 students in schools. We measured costs of vaccine, vaccine administration, and net program costs and used a validated Markov model to calculate the cost-effectiveness of the program. Vaccinating each student cost $44, $24 of which was the cost of vaccine administration. The net cost was $9 per person; considering productivity costs, net savings were $75 per person. Marginal cost per life year gained was $2100. Universal adolescent vaccination is also economically attractive in the United States but less attractive in regions with incidence rates below 3 cases per 100,000 per year. Hepatitis B vaccine can be delivered in North American schools at a reasonable cost. Adolescent vaccination is economically attractive in North American regions of high and average incidence rates. Our analysis supports vaccination in adolescents who remain at risk for hepatitis B virus infection.
    American Journal of Public Health 12/1998; 88(11):1638-44. · 3.93 Impact Factor
  • Article: Measuring health outcomes--putting gains into perspective.
    A S Detsky, D A Redelmeier
    New England Journal of Medicine 09/1998; 339(6):402-4. · 53.30 Impact Factor
  • Article: Shopping around for hospital services: a comparison of the United States and Canada.
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    ABSTRACT: Historical comparisons indicate that US hospitals are more expensive than Canadian hospitals, but health care system reform might have changed the relative costs and timeliness of health care in the 2 countries. To estimate the price and convenience of selected hospital services in the United States and Canada for patients in 1997 had they paid out-of-pocket. Cross-sectional telephone survey conducted May 1996 to April 1997. The 2 largest acute care general hospitals from every city in the United States and Canada with a population greater than 500000. Each hospital was telephoned and asked their price and waiting time for 7 services: magnetic resonance imaging of the head without gadolinium; a screening mammogram; a 12-lead electrocardiogram; a prothrombin time measurement; a session of hemodialysis; a screening colonoscopy; and a total knee replacement. Waiting times were measured in days until earliest appointment and charges were converted to American currency. Overall, 48 US and 18 Canadian hospitals were surveyed. Median waiting times were significantly shorter in American hospitals for 4 services, particularly a magnetic resonance imaging of the head (3 days vs 150 days; P<.001). Median charges were significantly higher in American hospitals for 6 services, particularly for a total knee replacement ($26805 vs $10651; P<.001). Individual services showed no association between shorter waiting times and higher prices within each country, with the exception of a total knee replacement in the United States. US hospitals still provide higher prices and faster care than Canadian hospitals for patients who pay out-of-pocket.
    JAMA The Journal of the American Medical Association 04/1998; 279(13):1015-7. · 30.03 Impact Factor
  • Article: Conflict of interest in the debate over calcium-channel antagonists.
    H T Stelfox, G Chua, K O'Rourke, A S Detsky
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    ABSTRACT: Physicians' financial relationships with the pharmaceutical industry are controversial because such relationships may pose a conflict of interest. It is unknown to what extent industry support of medical education and research influences the opinions and behavior of clinicians and researchers. The recent debate over the safety of calcium-channel antagonists provided an opportunity to examine the effect of financial conflicts of interest. We searched the English-language medical literature published from March 1995 through September 1996 for articles examining the controversy about the safety of calcium-channel antagonists. Articles were reviewed and classified as being supportive, neutral, or critical with respect to the use of calcium-channel antagonists. The authors of the articles were asked about their financial relationships with both manufacturers of calcium-channel antagonists and manufacturers of competing products (i.e., beta-blockers, angiotensin-converting-enzyme inhibitors, diuretics, and nitrates). We examined the authors' published positions on the safety of calcium-channel antagonists according to their financial relationships with pharmaceutical companies. Authors who supported the use of calcium-channel antagonists were significantly more likely than neutral or critical authors to have financial relationships with manufacturers of calcium-channel antagonists (96 percent, vs. 60 percent and 37 percent, respectively; P<0.001). Supportive authors were also more likely than neutral or critical authors to have financial relationships with any pharmaceutical manufacturer, irrespective of the product (100 percent, vs. 67 percent and 43 percent, respectively; P< 0.001). Our results demonstrate a strong association between authors' published positions on the safety of calcium-channel antagonists and their financial relationships with pharmaceutical manufacturers. The medical profession needs to develop a more effective policy on conflict of interest. We support complete disclosure of relationships with pharmaceutical manufacturers for clinicians and researchers who write articles examining pharmaceutical products.
    New England Journal of Medicine 01/1998; 338(2):101-6. · 53.30 Impact Factor
  • Article: Surgery versus stereotactic radiosurgery for small, operable cerebral arteriovenous malformations: a clinical and cost comparison.
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    ABSTRACT: Cerebral arteriovenous malformations (AVMs) may cause stroke and death in young patients. For small AVMs, the major curative treatment options are surgery and stereotactic radiosurgery (SR). Although the initial costs and risks of SR are less, there is a latency to cure and ultimately the success rate is lower than with surgery. Thus, these two treatment modalities were compared with respect to clinical outcomes and associated costs by means of a cost-effectiveness analysis. A decision analysis model was developed using Smltree software (J.P. Hollenberg, Roslyn, NY). Probability estimates for cure and complications for both therapies were derived from the literature. Utility values for minor and major stroke were measured in patients with AVMs who were treated at the University of Toronto clinic, using the standard gamble technique. Costs were obtained from several sources, including the case costing systems of several hospitals in Ontario, Canada. Surgery confers a 0.98 quality-adjusted life year (QALY) advantage over SR, at an additional cost of $6937 per patient. Thus, from a societal perspective, the incremental cost-effectiveness ratio is $7100 per QALY for a patient treated surgically. The result is sensitive to only two variables: surgical morbidity and surgical mortality. However, the preferred treatment strategy changes to favor SR only at the extreme high end of the possible range for these variables, when the rate of permanent neurological morbidity resulting from surgery exceeds 12% or the surgical mortality rate exceeds 4%. In the treatment of small AVMs, surgery confers a large clinical benefit over SR. The reason is that surgery protects the patient from hemorrhage earlier and with greater success than does SR. The associated cost-effectiveness ratio, $7100/QALY, is highly economically attractive. Therefore, surgery achieves important improvements in clinical outcomes and is associated with an excellent ratio of incremental costs per QALY gained.
    Neurosurgery 11/1997; 41(4):757-64; discussion 764-6. · 2.79 Impact Factor
  • Article: Perioperative assessment and management of risk from coronary artery disease.
    V A Palda, A S Detsky
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    ABSTRACT: To summarize available evidence on preoperative cardiac risk stratification so that the internist may 1) use clinical and electrocardiographic findings to stratify a patient's perioperative risk for myocardial infarction and death; 2) decide which tests provide useful additional risk-related information; and 3) understand the benefits, risks, and evidence surrounding the decision to undertake coronary revascularization before elective noncardiac surgery. A MEDLINE search and review of the reference lists of identified articles. Sensitivities, specificities, and likelihood ratios for diagnostic tests were calculated, and a quality rating for study methods was applied. Myocardial infarction and mortality were the major outcomes considered, and a quality rating for study methods was applied. Clinical and electrocardiographic findings, organized by multivariate prediction indices, accurately identify patients as having low, intermediate, or high risk for myocardial infarction or death. Pharmacologic stress imaging with thallium or echocardiography probably improves risk stratification for intermediate-risk patients having vascular surgery. These tests have not been shown to be effective prognostic indicators for patients having nonvascular surgery. No studies of angiography for risk prediction have been reported. Decision analyses and retrospective series suggest that the risks incurred by doing coronary angiography and revascularization before elective surgery outweigh the benefits. Prospective, controlled studies of coronary revascularization are lacking. Evidence from a randomized, controlled trial has shown a survival benefit with the perioperative use of beta-blockers in patients at risk for coronary artery disease. Evaluation of all surgical patients by use of clinical indices is recommended. Low-risk patients need no further evaluation before surgery. High-risk patients need optimal management of their high-risk problems, including (if appropriate) beta-blocker use, and may need to have their elective procedures canceled. Intermediate-risk patients probably benefit from further noninvasive stress testing, especially if they are having vascular surgery. Further clinical trials are needed for most areas of concern.
    Annals of internal medicine 09/1997; 127(4):313-28. · 16.73 Impact Factor
  • Article: Atenolol before and after non-cardiac surgery reduced mortality and cardiovascular morbidity in patients at risk of acute coronary events.
    V A Palda, A S Detsky
    Evidence-based Cardiovascular Medicine 07/1997; 1(2):55-6.
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    Article: The cost-effectiveness of magnetic resonance imaging for patients with equivocal neurological symptoms.
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    ABSTRACT: To determine the incremental cost-effectiveness of magnetic resonance imaging (MRI) and computed tomography (CT) in young adults presenting with equivocal neurological signs and symptoms. A decision analysis of long-term survival using accuracy data from a diagnostic technology assessment of MRI and CT in patients with suspected multiple sclerosis, information from the medical literature, and clinical assumptions. In the baseline analysis, at 30% likelihood of an underlying neurologic disease, MRI use has an incremental cost of $101,670 for each additional quality-adjusted life-year saved compared with $20,290 for CT use. As the probability of disease increases, further MRI use becomes a cost-effective alternative costing $30,000 for each quality-adjusted life-year saved. If a negative MRI result provides reassurance, the incremental costs of immediate MRI use decreases and falls below $25,000 for each quality-adjusted life-year saved no matter the likelihood of disease. For most individuals with neurological symptoms or signs, CT imaging is cost-effective while MR imaging is not. The cost-effectiveness of MRI use, however, improves as the likelihood of an underlying neurological disease increases. For selected patients who highly value diagnostic information, MRI is a reasonable and cost-effective use of medical resources when even the likelihood of disease is quite low (5%).
    International Journal of Technology Assessment in Health Care 02/1997; 13(1):21-34. · 1.37 Impact Factor
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    Article: The relation of conjunctival pallor to the presence of anemia.
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    ABSTRACT: To determine the value of conjunctival pallor in ruling in or ruling out the presence of severe anemia (hemoglobin < or = 90 g/L) and to determine the interobserver agreement in assessing this sign. Patients were prospectively assessed for pallor by at least one of three observers. All observations were made without information of the patient's hemoglobin value or of another observer's assessment. Tertiary-care, university-affiliated teaching hospital. Three hundred and two medical and surgical inpatients. Likelihood ratios (LRs) calculated for conjunctival pallor present, borderline, and absent were as follows: pallor present, LR 4.49 (95% confidence interval [CI] 1.80, 10.99); pallor borderline, LR 1.80 (95% CI 1.18, 2.62); pallor absent, LR 0.61 (95% CI 0.44, 0.80). Kappa scores of interobserver agreement between paired observers were 0.75 and 0.54. The presence of conjunctival pallor, without other information suggesting anemia, is reason enough to perform a hemoglobin determination. The absence of conjunctival pallor is not likely to be of use in ruling out severe anemia. With well-defined criteria, interobserver agreement is good to very good.
    Journal of General Internal Medicine 02/1997; 12(2):102-6. · 2.83 Impact Factor
  • Article: Working with Markov processes
    Medical Decision Making. 01/1997; 17:152-159 ST - Working with Markov processes.
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    Article: Cost comparison of molecular versus conventional screening of relatives at risk for retinoblastoma.
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    ABSTRACT: To compare costs of molecular and conventional screening of retinoblastoma relatives, we evaluated the direct health care costs. With variables set at the most likely values (baseline), the expected cost (in 1994 Canadian dollars) of conventional screening was $31,430 for a prototype family consisting of seven at-risk relatives (three clinic exams and eight examinations under anaesthetic over the first 3 years of life for each relative). For the molecular strategy that involves looking for the RB1 gene mutation in the proband, testing the relatives for that mutation, and clinical follow-up similar to conventional strategy for relatives with mutation, the expected cost was $8,674, using baseline variables. Sensitivity analysis over the range of values for each variable revealed a significant saving of health care dollars by the molecular route, indicating the benefit of redirecting economic resources to molecular diagnosis in retinoblastoma.
    The American Journal of Human Genetics 09/1996; 59(2):301-7. · 10.60 Impact Factor
  • Article: The effect of spectrum bias on the utility of magnetic resonance imaging and evoked potentials in the diagnosis of suspected multiple sclerosis.
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    ABSTRACT: Spectrum bias is the tendency for the effectiveness of a test (or treatment) to vary as a function of clinical, pathologic, or comorbid variables including disease severity. Our null hypothesis was that within the population of suspected multiple sclerosis (MS) patients, there would be no difference in MRI and evoked potential (EP) sensitivity and specificity between those with mild MS versus those with more severe clinical signs of the disease, i.e., that spectrum bias is not a factor. Three hundred three patients with suspected MS were evaluated by a board-certified neurologist, then scanned with MRI. Two hundred four patients also received EP testing. The sensitivity of MRI in patients with suspected MS was 58 percent with a false-positive rate of 9%. The overall sensitivity was 64% in the probable and 45% in the possible group. In the low pretest probability group sensitivity was 20%, and it was 70% in the high pretest probability group. These differences in sensitivity are statistically significant (p < 0.03). In contrast, the specificity between groups did not differ significantly. EP sensitivity was 69% in the high probability subgroup and 5% in the low probability subgroup. (p < 0.01). In this study, both EP and MRI results demonstrated an association between disease frequency, disease severity, and test sensitivity with greater disease frequency and intensity suggesting more impressive diagnostic test performance. The distorting effect of the variable clinical severity on MRI and EP sensitivity in suspected MS underscores that diagnostic tests perform differently in different groups of patients.
    Neurology 08/1996; 47(1):140-4. · 8.31 Impact Factor
  • Article: Cost-effectiveness analysis of potential improvements to emergency medical services for victims of out-of-hospital cardiac arrest.
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    ABSTRACT: To measure the incremental cost-effectiveness of various improvements to emergency medical services (EMS) systems aimed at increasing survival after out-of-hospital cardiac arrest. We performed cost-effectiveness analysis based on (1) metaanalysis of effectiveness of the various EMS systems, (2) costing of each component of EMS systems, (3) modeling of the relationship between the proportion of cardiac arrest victims who receive CPR and the proportion of individuals trained, (4) modeling of the relationship between response time interval and the characteristics of the EMS system, (5) measurement of quality of life, and (6) decision analysis to combine the results of the first five components. The incremental cost-effectiveness ratio for a 48-second improvement in mean response time in a one-tier EMS system yielded by the addition of more EMS providers was $368,000 per quality-adjusted life year (QALY). For improved response time in a two-tier EMS system by the addition of more basic life support (BLS)/BLS-defibrillator (BLS-D) providers to the first tier, the ratio was $53,000 per QALY with pump vehicles or $159,000 per QALY with ambulances. Change from a one-tier EMS to a two-tier EMS system by the addition of initial BLS/BLS-D providers in pump vehicles as the first tier was associated with a cost per QALY of $40,000. Change from one-tier EMS to two-tier EMS by the addition of initial BLS/BLS-D providers in ambulances as the first tier was associated with a cost per QALY of $94,000. The most attractive options in terms of incremental cost-effectiveness were improved response time in a two-tier EMS system or change from a one-tier to a two-tier EMS system. Future research should be directed toward identification of the costs of instituting the first tier of a two-tier EMS system and identification of cost-effective methods of improving response time.
    Annals of Emergency Medicine 07/1996; 27(6):711-20. · 4.13 Impact Factor
  • Article: Effectiveness of emergency medical services for victims of out-of-hospital cardiac arrest: a metaanalysis.
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    ABSTRACT: To determine the relative effectiveness of differences in response time interval, proportion of bystander CPR, and type and tier of emergency medical services (EMS) system on survival after out of hospital cardiac arrest. We performed a comprehensive literature search, excluding EMS systems other than those of interest (systems of interest were those comprising one tier with providers of basic life support [BLS] or advanced life support [ALS] and those comprising two tiers with providers of BLS or BLS-defibrillation followed by ALS), patient population of fewer than 100 cardiac arrests, studies in which we could not determine the total number of arrests of presumed cardiac origin, and studies lacking data on survival to hospital discharge. Metaanalysis using generalized linear model with dispersion estimation for random effects was then performed. Increased survival to hospital discharge was significantly associated with tier (P < .01), response time interval (P < .01), and bystander CPR (P = .04). A significant interaction was detected between response time interval and bystander CPR (P = .02). For the studies analyzed, survival was 5.2% in a one-tier EMS system or 10.5% in a two-tier EMS system. A 1-minute decrease in mean response time interval was associated with absolute increases in survival rates of .4% and .7% in a one-tier and two-tier EMS systems, respectively. Increased survival to hospital discharge may be associated with decreased response time interval and with the use of a two-tier EMS system as opposed to a one-tier system. The data available for this analysis were suboptimal. Policymakers need more methodologically rigorous research to have more reliable and valid estimates of the effectiveness of different EMS systems.
    Annals of Emergency Medicine 06/1996; 27(6):700-10. · 4.13 Impact Factor
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    Article: Direct and indirect costs of asthma in Canada, 1990.
    M D Krahn, C Berka, P Langlois, A S Detsky
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    ABSTRACT: To calculate the direct and indirect costs of asthma in Canada. Cost-of-illness study. Canada. All Canadians receiving inpatient or outpatient care for asthma in 1990. Direct costs incurred by inpatient care, emergency services, physician and nursing services, ambulance use, drugs and devices, outpatient diagnostic tests, research and education. Indirect costs from productivity loss due to absence from work, inability to to perform housekeeping activities, need to care for children with asthma who were absent from school, time spent travelling and waiting for medical care, and premature death from asthma. All costs are in 1990 Canadian dollars. Depending on assumptions, the total cost of asthma was estimated to be between $504 million and $648 million. Direct costs were $306 million. The single largest component of direct costs was the cost of drugs ($124 million). The largest component of indirect costs was illness-related disability ($76 million). Annual costs of treating asthma are comparable to the individual cost of infectious diseases, hematological diseases, congenital defects, perinatal illnesses, home care and ambulance services. Asthma costs may increase in the future, given current morbidity and mortality trends. Further evaluation of the effectiveness and cost-effectiveness of available asthma interventions in addition to aggregate cost data are required to determine whether resource allocation for the treatment of asthma can be improved.
    Canadian Medical Association Journal 04/1996; 154(6):821-31. · 8.22 Impact Factor

Institutions

  • 1983–1998
    • University of Toronto
      • • Department of Medicine
      • • Faculty of Medicine
      Toronto, Ontario, Canada
  • 1996
    • The Ottawa Hospital
      Ottawa, Ontario, Canada
  • 1994
    • University of Rochester
      Rochester, NY, USA
  • 1992
    • The Princess Margaret Hospital
      Toronto, Ontario, Canada
  • 1990
    • UHN: Toronto General Hospital
      Toronto, Ontario, Canada
    • Sunnybrook Health Sciences Centre
      Toronto, Ontario, Canada