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1.  Understanding the costs of cancer care before and after diagnosis for the 21 most common cancers in Ontario: a population-based descriptive study 
CMAJ Open  2013;1(1):E1-E8.
Background
The first year after cancer diagnosis is a period of intensive treatment and high cost. We sought to estimate costs for the 21 most common cancers in Ontario in the 3-month period before and the first year after diagnosis.
Methods
We used the Ontario Cancer Registry to select patients who received diagnoses between 1997 and 2007 at 19 years of age or older, with valid International Classification of Diseases for Oncology (ICD-O) and histology codes, who survived 30 days or longer after diagnosis and had no second cancer within 90 days of the initial cancer (n = 402 399). We used linked administrative data to calculate mean costs for each cancer during the pre- and postdiagnosis periods for patients who died within 1 year after diagnosis and patients who survived beyond 1 year after diagnosis.
Results
Mean prediagnosis costs were $2060 (95% confidence interval [CI] $2023–$2098) for all patients with cancer. Costs ranged from $890 (95% CI $795–$985) for melanoma to $4128 (95% CI $3591–$4664) for liver cancer among patients who survived beyond 1 year after diagnosis, and ranged from $2188 (95% CI $2040–$2336) for esophageal cancer to $5142 (95% CI $4664–$5620) for multiple myeloma among patients who died within 1 year. The mean postdiagnosis cost for our cohort was $25 914 (95% CI $25 782–$26 046). Mean costs were lowest for melanoma ($8611 [95% CI $8221–$9001]) and highest for esophageal cancer ($50 620 [95% CI $47 677–$53 562] among patients who survived beyond 1 year after diagnosis, and ranged from $27 560 (95% CI $25 747–$29 373) for liver cancer to $81 655 (95% CI $58 361–$104 949) for testicular cancer among patients who died within 1 year.
Interpretation
Our research provides cancer-related cost estimates for the pre- and postdiagnosis phases and offers insight into the economic burden incurred by the Ontario health care system. These estimates can help inform policy-makers’ decisions regarding resource allocation for cancer prevention and control, and can serve as important input for economic evaluations.
doi:10.9778/cmajo.20120013
PMCID: PMC3985946  PMID: 25077097
2.  Trends in use and cost of initial cancer treatment in Ontario: a population-based descriptive study 
CMAJ Open  2013;1(4):E151-E158.
Background
Cancer incidence and treatment-related costs are rising in Canada. We estimated health care use and costs in the first year after diagnosis for patients with 7 common types of cancer in Ontario to examine temporal trends in patterns of care and costs.
Methods
We selected patients aged 19–44 years who had received a diagnosis of melanoma, breast cancer (female only), testicular cancer or thyroid cancer, in addition to patients aged 45 years and older who had received a diagnosis of breast (female only), prostate, lung or colorectal cancer, between 1997 and 2007. Patients were identified from the Ontario Cancer Registry. Using linked administrative databases, we determined use and costs of chemotherapy, radiotherapy, cancer-related surgery, other admissions to hospital and home care. We adjusted all costs to 2009 Canadian dollars.
Results
We identified 20 821 patients aged 19–44 years and 178 797 patients aged 45 years and older. The greatest increases in costs during the study period were for melanoma, breast cancer, colorectal cancer, lung cancer and prostate cancer (p < 0.05). For prostate and lung cancers, mean costs increased 50% (from $11 490 and $22 037 to $15 170 and $34 473, respectively). Mean costs doubled for breast (from $15 460 and $12 909 to $35 977 and $29 362 for younger and older patients, respectively) and colorectal cancers (from $24 769 to $43 964), and nearly tripled for melanoma (from $3581 to $8934). Costs related to hospital admissions accounted for the largest portion of total costs. The use of chemotherapy, radiotherapy and home care generally increased for all cancers.
Interpretation
The significant increase in mean costs of initial cancer treatment among the patients included in this study was primarily due to more patients receiving adjuvant therapy and home care, and to the increasing expenditures for these services and cancer-related surgeries. Understanding trends in health care use and costs can help policy-makers to take the necessary measures to achieve a more accountable, high-performing health care system.
doi:10.9778/cmajo.20130041
PMCID: PMC3986020  PMID: 25077117
3.  Estimating the payoffs from cardiovascular disease research in Canada: an economic analysis 
CMAJ Open  2013;1(2):E83-E90.
Background
Investments in medical research can result in health improvements, reductions in health expenditures and secondary economic benefits. These “returns” have not been quantified in Canada. Our objective was to estimate the return on cardiovascular disease research funded by public or charitable organizations.
Methods
Our primary outcome was the internal rate of return on cardiovascular disease research funded by public or charitable sources. The internal rate of return is the annual monetary benefit to the economy for each dollar invested in cardiovascular disease research. Calculation of the internal rate of return involved the following: measuring expenditures on cardiovascular disease research, estimating the health gains accrued from new treatments for cardiovascular disease, determining the proportion of health gains attributable to cardiovascular disease research and the time lag between research expenditures and health gains, and estimating the spillovers from public- or charitable-sector investments to other sectors of the economy.
Results
Expenditures by public or charitable organizations on cardiovascular disease research from 1981 to 1992 amounted to $392 million (2005 dollars). Health gains associated with new treatments from 1994 to 2005 (13-yr lag) amounted to 2.2 million quality-adjusted life-years. We calculated an internal rate of return of 20.6%.
Conclusion
Canadians obtain relatively high health and economic gains from investments in cardiovascular disease research. Every $1 invested in cardiovascular disease research by public or charitable sources yields a stream of benefits of roughly $0.21 to the Canadian economy per year, in perpetuity.
doi:10.9778/cmajo.20130003
PMCID: PMC3986018  PMID: 25077108
4.  Predictors of antiviral therapy in a post-transfusion cohort of hepatitis C patients 
INTRODUCTION
In the past, antiviral therapy has been given to 15% to 30% of patients infected with hepatitis C virus (HCV). The efficacy of therapy has recently improved with the addition of ribavirin and pegylated interferon. The aim of the present study was to identify the clinical, socioeconomic and health-system predictors of antiviral treatment for HCV.
METHODS
A retrospective analysis of compensation claims data of patients who acquired HCV through blood transfusions between 1986 and 1990 was performed. The patients consisted of 2456 Canadian HCV-positive individuals. The authors reviewed narrative comments from physicians, and constructed univariate and multivariate logistic regression models, using receipt of antiviral therapy with interferon or interferon/ribavirin as the primary outcome.
RESULTS
Of the 2456 patients, approximately 30% appeared to be eligible, but only 16% received treatment. Univariate analyses suggested that the disease severity, age, HIV status and province of residence were associated with the likelihood of receiving treatment (P<0.01). The final, multivariable model indicated that in patients with HCV: intermediate disease severity (eg, fibrosis, P<0.0001); middle age (P<0.0001); HIV-negative status (P<0.0001); and province of residence (Quebec, P<0.0001; and Saskatchewan, P<0.0001) were independent predictors of treatment. Narrative comments of physicians emphasized the importance of age, HIV status and patient preferences in clinical decision-making.
DISCUSSION
Given the efficacy and cost-effectiveness of current antiviral therapy, treatment rates of HCV patients may be suboptimal. Further work is required to understand barriers to treatment related to geography, organization of medical care, age, medical provider and patient preferences.
PMCID: PMC2538973  PMID: 16482237
Antiviral therapy; Comorbidity; Hepatitis C
5.  Economic analysis of Heart and Stroke Foundation of Ontario’s Hypertension Management Initiative 
Objectives
Hypertension is suboptimally treated in primary care settings. We evaluated the cost-effectiveness of the Heart and Stroke Foundation of Ontario’s Hypertension Management Initiative (HMI), an interdisciplinary, evidence-informed chronic disease management model for primary care that focuses on improving blood pressure management and control by primary care providers and patients according to clinical best practice guidelines.
Methods
The perspective of our analysis was that of the Ontario Ministry of Health and Long-Term Care with a lifetime horizon and 5% annual discount rate. Using data from a prospective cohort study from the HMI, we created two matched groups: pre-HMI (standard care), and post-HMI (n = 1720). For each patient, we estimated the 10-year risk of cardiovascular disease (CVD) using the Framingham risk equation and life expectancy from life tables. Long-term health care costs incurred with physician visits, acute and chronic care hospitalizations, emergency department visits, same-day surgeries, and medication use were determined through linkage to administrative databases, using a bottom-up approach.
Results
The HMI intervention was associated with significant reductions in systolic blood pressure (126 mmHg vs 134 mmHg with standard care; P-value < 0.001). These improvements were associated with a reduction in the 10-year risk of CVD (9.5% risk vs 10.7% in standard care; P-value < 0.001) and a statistically significant improvement in discounted life expectancy (9.536 years vs 9.516 in standard care; P-value < 0.001). The HMI cohort had a discounted mean lifetime cost of $22,884 CAD vs $22,786 CAD for standard care, with an incremental cost-effectiveness ratio of $4939 CAD per life-year gained.
Conclusion
We found that the HMI is a cost-effective means of providing evidence-informed, chronic disease management in primary care to patients with hypertension.
doi:10.2147/CEOR.S33390
PMCID: PMC3501398  PMID: 23180969
hypertension; economic evaluation; cardiovascular disease
6.  How much are we spending? The estimation of research expenditures on cardiovascular disease in Canada 
Background
Cardiovascular disease (CVD) is a leading cause of death in Canada and is a priority area for medical research. The research funding landscape in Canada has changed quite a bit over the last few decades, as have funding levels. Our objective was to estimate the magnitude of expenditures on CVD research for the public and charitable (not-for profit) sectors in Canada between 1975 and 2005.
Methods
To estimate research expenditures for the public and charitable sectors, we compiled a complete list of granting agencies in Canada, contacted each agency and the Canadian Institutes of Health Research (CIHR), and extracted data from the organizations’ annual reports and the Reference Lists of health research in Canada. Two independent reviewers scanned all grant and fellowship/scholarship titles (and summary/key words, when available) of all research projects funded to determine their inclusion in our analysis; only grants and fellowships/scholarships that focused on heart and peripheral vascular diseases were selected.
Results
Public/charitable sector funding increased 7.5 times, from close to $13 million (in constant dollars) in 1975 to almost $96 million (in constant dollars) in 2005 (base year). The Medical Research Council of Canada (MRCC)/CIHR and the Heart & Stroke Foundation of Canada have been the main founders of this type of research during our analysis period; the Alberta Heritage Foundation for Medical Research and the Fonds de la recherche en santé du Quebec have played major roles at the provincial level. The Indirect Costs Research Program and Canada Foundation for Innovation have played major roles in terms of funding in the last years of our analysis.
Conclusion
Public/charitable-funded research expenditures devoted to CVD have increased substantially over the last three decades. By international standards, the evidence suggests Canada spends less on health-related research than the UK and the US, at least in absolute terms. However, this may not be too problematic as Canada is likely to free-ride from research undertaken elsewhere. Understanding these past trends in research funding may provide decision makers with important information for planning future research efforts. Future work in this area should include the use of our coding methods to obtain estimates of funded research for other diseases in Canada.
doi:10.1186/1472-6963-12-281
PMCID: PMC3469373  PMID: 22929001
Cardiovascular disease; Research expenditures; Health policy
7.  Influence of Socioeconomic Status on Survival of Hepatocellular Carcinoma in the Ontario Population; A Population-Based Study, 1990–2009 
PLoS ONE  2012;7(7):e40917.
Background
Research has shown that people from higher socioeconomic status (SES) have better hepatocellular carcinoma (HCC) survival outcomes, although no such research has been carried out in Canada. We aimed to assess if an association between SES and HCC survival existed in the Canadian context.
Methodology/Prinicpal Findings
We conducted a population-based cohort study linking HCC cases identified in the Ontario Cancer Registry between 1990 and 2009 to administrative and hospital data. Logistic regression and chi-squared tests were used to evaluate associations between SES (income quintile) and covariates. The Kaplan-Meier method was used to estimate survival. Sequential analysis of the proportional-hazards models were used to determine the association between SES and HCC survival controlling for potential prognostic covariates. During the period 1990–2009, 5,481 cases of HCC were identified. A significant association was found between SES and curative treatment (p = 0.0003), but no association was found between SES and non-curative treatment (p = 0.064), palliative treatment (p = 0.680), or ultrasound screening (p = 0.615). The median survival for the lowest SES was 8.5 months, compared to 8.8 months for the highest SES group. The age- and sex-adjusted proportional-hazards model showed statistically significant difference in HCC survival among the SES groups, with hazard ratio 0.905 (95% confidence intervals 0.821, 0.998) when comparing highest to lowest SES group. Further adjustments indicated that potentially curative treatment was the likely explanation for the association between SES and HCC survival.
Conclusions/Significance
Our findings suggest that a 10% HCC survival advantage exists for the higher SES groups. This association between SES and HCC survival is most likely a reflection of lack of access to care for low SES groups, revealing inequities in the Canadian healthcare system.
doi:10.1371/journal.pone.0040917
PMCID: PMC3396620  PMID: 22808283
8.  End-of-Life Care for Lung Cancer Patients in the United States and Ontario 
Background
Both the United States and Canada offer government-financed health insurance for the elderly, but few studies have compared care at the end of life for cancer patients between the two systems.
Methods
We identified care for non–small cell lung cancer (NSCLC) patients who died of cancer at age 65 years and older during 1999–2003. Patients were identified from US Surveillance, Epidemiology, and End Results (SEER)–Medicare data (N = 13 533) and the Ontario Cancer Registry (N = 8100). Health claims during the last 5 months of life identified chemotherapy and emergency room use, hospitalizations, and supportive care. We estimated rates per person-months (PM) for short-term survivors (died <6 months after diagnosis) and longer-term survivors (died ≥6 months after diagnosis), adjusting for demographic differences. To test whether monthly rates in Ontario were statistically significantly different from the United States, standardized differences were computed, and a 99% confidence interval (CI) was constructed to account for the multiple tests performed. All statistical tests were two-sided.
Results
Rates of chemotherapy use were statistically significantly higher for SEER–Medicare patients than Ontario patients in every month before death (short-term survivors at 5 months before death: SEER–Medicare, 33.2 patients per 100 PM vs Ontario, 9.5 per 100 PM, rate difference = 23.7 per 100 PM, 99% CI = 18.3 to 29.1 per 100 PM, P < .001; longer-term survivors at 5 months before death: SEER–Medicare, 24.4 patients per 100 PM vs Ontario, 14.5 per 100 PM, rate difference = 9.9 per 100 PM, 99% CI = 7.7 to 12.1 per 100 PM, P <. 001). During the last 30 days of life, fewer SEER–Medicare than Ontario patients were hospitalized (short-term survivors, 49.9 vs 78.6 patients per 100 PM, rate difference = 28.6 per 100 PM, 95% CI = 22.9 to 34.4 per 100 PM, P <. 001; longer-term survivors, 44.1 vs 67.1 patients per 100 PM, rate difference = 23.0 per 100 PM, 95% CI = 18.5 to 27.5 per 100 PM, P < .001).
Conclusions
NSCLC patients in both Ontario and the United States used extensive end-of-life care. Limited availability of hospice care in Ontario and differing attitudes between the United States and Ontario regarding end-of-life care may explain the differences in practice patterns.
doi:10.1093/jnci/djr145
PMCID: PMC3115676  PMID: 21593012
10.  Techniques for estimating health care costs with censored data: an overview for the health services researcher 
Objective
The aim of this study was to review statistical techniques for estimating the mean population cost using health care cost data that, because of the inability to achieve complete follow-up until death, are right censored. The target audience is health service researchers without an advanced statistical background.
Methods
Data were sourced from longitudinal heart failure costs from Ontario, Canada, and administrative databases were used for estimating costs. The dataset consisted of 43,888 patients, with follow-up periods ranging from 1 to 1538 days (mean 576 days). The study was designed so that mean health care costs over 1080 days of follow-up were calculated using naïve estimators such as full-sample and uncensored case estimators. Reweighted estimators – specifically, the inverse probability weighted estimator – were calculated, as was phase-based costing. Costs were adjusted to 2008 Canadian dollars using the Bank of Canada consumer price index (http://www.bankofcanada.ca/en/cpi.html).
Results
Over the restricted follow-up of 1080 days, 32% of patients were censored. The full-sample estimator was found to underestimate mean cost ($30,420) compared with the reweighted estimators ($36,490). The phase-based costing estimate of $37,237 was similar to that of the simple reweighted estimator.
Conclusion
The authors recommend against the use of full-sample or uncensored case estimators when censored data are present. In the presence of heavy censoring, phase-based costing is an attractive alternative approach.
doi:10.2147/CEOR.S31552
PMCID: PMC3377439  PMID: 22719214
health care costing; heart failure; incomplete data; statistical techniques; phase-based costing
11.  How Well Do Guidelines Incorporate Evidence on Patient Preferences? 
ABSTRACT
BACKGROUND
Clinical practice guidelines (CPG) are meant to consider important values such as patient preferences.
OBJECTIVE
To assess how well clinical practice guidelines (CPGs) integrate evidence on patient preferences compared with that on treatment effectiveness.
DESIGN
A cross-sectional review of a listing in 2006 of CPGs judged to be the best in their fields by an external joint government and medical association body.
STUDY SELECTION
Exclusion criterion was unavailability in electronic format. Sixty-five of 71 listed CPGs met selection criteria.
MEASUREMENTS
Two instruments originally constructed to evaluate the overall quality of CPGs were adapted to specifically assess the quality of integrating information on patient preference vs. treatment effectiveness. Counts of words and references in each CPG associated with patient preferences vs. treatment effectiveness were performed. Two reviewers independently assessed each CPG.
MAIN RESULTS
Based on our adapted instruments, CPGs scored significantly higher (p < 0.001) on the quality of integrating treatment effectiveness compared with patient preferences evidence (mean instrument one scores on a scale of 0.25 to 1.00: 0.65 vs. 0.43; mean instrument two scores on a scale of 0 to 1: 0.58 vs. 0.18). The average percentage of the total word count dedicated to treatment effectiveness was 24.2% compared with 4.6% for patient preferences. The average percentage of references citing treatment effectiveness evidence was 36.6% compared with 6.0% for patient preferences.
CONCLUSION
High quality CPGs poorly integrate evidence on patient preferences. Barriers to incorporating preference evidence into CPGs should be addressed.
Electronic supplementary material
The online version of this article (doi:10.1007/s11606-009-0987-8) contains supplementary material, which is available to authorized users.
doi:10.1007/s11606-009-0987-8
PMCID: PMC2710487  PMID: 19387746
clinical practice guidelines; evidence-based medicine; preference; decision analysis; qualitative research
12.  Health status utilities and the impact of pressure ulcers in long-term care residents in Ontario 
Quality of Life Research  2009;19(1):81-89.
Purpose
To estimate health status utilities in long-term care (LTC) residents in Ontario, both with and without pressure ulcers (PUs), and to determine the impact of PU on health-related quality of life (HRQOL).
Methods
A retrospective population-based study was carried out using Minimum Data Set (MDS) health assessment data among all residents in 89 LTC homes in Ontario who had a full MDS assessment between May 2004 and November 2007. The Minimum Data Set-Health Status Index (MDS-HSI) was used to measure HRQOL. A stepwise regression was used to determine the impact of PU on MDS-HSI scores.
Results
A total of 1,498 (9%) of 16,531 LTC residents had at least one stage II PU or higher. The mean ± SD MDS-HSI scores of LTC residents without PU and those with PU were 0.36 ± 0.17 and 0.26 ± 0.13, respectively (p < 0.001). Factors associated with lower MDS-HSI scores included: older age; being female; having a PU; recent hip fracture; multiple comorbid conditions; bedfast; incontinence; Changes in Health, End-stage disease and Symptoms and Signs; clinically important depression; treated with a turning/repositioning program; taking antipsychotic medications; and use of restraints.
Conclusions
LTC residents with PU had slightly though statistically significantly lower HRQOL than those without PU. Comorbidity contributed substantially to the low HRQOL in these populations. Community-weighted MDS-HSI utilities for LTC residents are useful for cost-effectiveness analyses and help guide health policy development.
doi:10.1007/s11136-009-9563-2
PMCID: PMC2804787  PMID: 20033300
Health-related quality of life; Long-term care; Minimum Data Set; Health Status Index; Ontario/Canada; Utilities
13.  Modelling mitigation strategies for pandemic (H1N1) 2009 
Background
The 2009 influenza A (H1N1) pandemic has required decision-makers to act in the face of substantial uncertainties. Simulation models can be used to project the effectiveness of mitigation strategies, but the choice of the best scenario may change depending on model assumptions and uncertainties.
Methods
We developed a simulation model of a pandemic (H1N1) 2009 outbreak in a structured population using demographic data from a medium-sized city in Ontario and epidemiologic influenza pandemic data. We projected the attack rate under different combinations of vaccination, school closure and antiviral drug strategies (with corresponding “trigger” conditions). To assess the impact of epidemiologic and program uncertainty, we used “combinatorial uncertainty analysis.” This permitted us to identify the general features of public health response programs that resulted in the lowest attack rates.
Results
Delays in vaccination of 30 days or more reduced the effectiveness of vaccination in lowering the attack rate. However, pre-existing immunity in 15% or more of the population kept the attack rates low, even if the whole population was not vaccinated or vaccination was delayed. School closure was effective in reducing the attack rate, especially if applied early in the outbreak, but this is not necessary if vaccine is available early or if pre-existing immunity is strong.
Interpretation
Early action, especially rapid vaccine deployment, is disproportionately effective in reducing the attack rate. This finding is particularly important given the early appearance of pandemic (H1N1) 2009 in many schools in September 2009.
doi:10.1503/cmaj.091641
PMCID: PMC2774362  PMID: 19825923
14.  Health-state utilities in a prisoner population: a cross-sectional survey 
Background
Health-state utilities for prisoners have not been described.
Methods
We used data from a 1996 cross-sectional survey of Australian prisoners (n = 734). Respondent-level SF-36 data was transformed into utility scores by both the SF-6D and Nichol's method. Socio-demographic and clinical predictors of SF-6D utility were assessed in univariate analyses and a multivariate general linear model.
Results
The overall mean SF-6D utility was 0.725 (SD 0.119). When subdivided by various medical conditions, prisoner SF-6D utilities ranged from 0.620 for angina to 0.764 for those with none/mild depressive symptoms. Utilities derived by the Nichol's method were higher than SF-6D scores, often by more than 0.1. In multivariate analysis, significant independent predictors of worse utility included female gender, increasing age, increasing number of comorbidities and more severe depressive symptoms.
Conclusion
The utilities presented may prove useful for future economic and decision models evaluating prison-based health programs.
doi:10.1186/1477-7525-7-78
PMCID: PMC2741437  PMID: 19715571
15.  Management of solitary 1 cm to 2 cm liver nodules in patients with compensated cirrhosis: A decision analysis 
OBJECTIVES:
Current guidelines, based on expert opinion, recommend that suspected 1 cm to 2 cm hepatocellular carcinoma (HCC) detected on screening be biopsied and, if positive, treated (eg, resection or transplantation). Alternative strategies are immediate treatment or observation until disease progression occurs.
METHODS:
A Markov decision model was developed that compared three management strategies – immediate resection, biopsy and resection if positive, and ultrasound surveillance every three months until disease progression – for a single 1 cm to 2 cm liver nodule suspicious for HCC following ultrasound screening and computed tomography confirmation. The cohort included 55-year-old patients with compensated cirrhosis and no significant comorbidities. The model used in the present study incorporated the probabilities of false-positive and false-negative results, needle-track seeding, HCC recurrence, cirrhosis progression and death. The quality-adjusted life expectancy (LE) and the unadjusted LE were evaluated and the model’s strength was assessed with sensitivity analyses.
RESULTS:
In the base case analysis, biopsy, resection and surveillance yielded an unadjusted LE of 60.5, 59.7 and 56.6 months, respectively, and a quality-adjusted LE of 46.6, 45.6 and 43.8 months, respectively. In probabilistic sensitivity analyses, biopsy was the preferred strategy 69.5% of the time, resection 30.5% of the time and surveillance never. Resection was the optimal decision if the sensitivity of biopsy was very low (less than 0.45) or if the accuracy of the imaging tests resulted in a high percentage of HCC-positive patients (greater than 76%) in the screened cohort, as with expert interpretation of triphasic computed tomography.
CONCLUSIONS:
The present model suggests that biopsy is the preferred management strategy for these patients. When postimaging probability of HCC is high or pathology expertise is lacking, resection is the best alternative. Surveillance is never the optimal strategy.
PMCID: PMC2657973  PMID: 17703248
Decision analysis; Hepatic resection; Hepatocellular carcinoma; Liver cirrhosis
16.  Cohort effects in dynamic models and their impact on vaccination programmes: an example from Hepatitis A 
Background
Infection rates for many infectious diseases have declined over the past century. This has created a cohort effect, whereby older individuals experienced a higher infection rate in their past than younger individuals do now. As a result, age-stratified seroprevalence profiles often differ from what would be expected from constant infection rates.
Methods
Here, we account for the cohort effect by fitting an age-structured compartmental model with declining transmission rates to Hepatitis A seroprevalence data for Canadian-born individuals. We compare the predicted impact of universal vaccination with and without including the cohort effect in the dynamic model.
Results
We find that Hepatitis A transmissibility has declined by a factor of 2.8 since the early twentieth century. When the cohort effect is not included in the model, incidence and mortality both with and without vaccination are significantly over-predicted. Incidence (respectively mortality) over a 20 year period of universal vaccination is 34% (respectively 90%) higher than if the cohort effect is included. The percentage reduction in incidence and mortality due to vaccination are also over-predicted when the cohort effect is not included. Similar effects are likely for many other infectious diseases where infection rates have declined significantly over past decades and where immunity is lifelong.
Conclusion
Failure to account for cohort effects has implications for interpreting seroprevalence data and predicting the impact of vaccination programmes with dynamic models. Cohort effects should be included in dynamic modelling studies whenever applicable.
doi:10.1186/1471-2334-6-174
PMCID: PMC1702544  PMID: 17147828
17.  Preferences of Husbands and Wives for Outcomes of Prostate Cancer Screening and Treatment 
OBJECTIVE
To explore the preferences of male primary care patients and their spouses for the outcomes of prostate cancer screening and treatment, and quality of life with metastatic prostate cancer.
DESIGN
Cross-sectional design.
SETTING
Primary care clinics in Galveston County, Texas.
PATIENTS
One hundred sixty-eight couples in which the husband was a primary care patient and a candidate for prostate cancer screening.
MEASUREMENTS AND MAIN RESULTS
Preferences were measured as utilities for treatment outcomes and quality of life with metastatic disease by the time trade-off method for the husband and the wife individually and then conjointly for the couple. For each health state considered, husbands associated lower utilities for the health states than did their wives. Couples’ utilities fell between those of husbands and wives (all comparisons were significant at P < .01). For partial and complete impotence and mild-to-moderate incontinence, the median utility value for the wives was 1.0, indicating that most wives did not associate disutility with their husbands having to experience these treatment complications.
CONCLUSIONS
Male primary care patients who are candidates for prostate cancer screening evaluate the outcomes of prostate cancer treatment and life with advanced prostate cancer as being far worse than do their wives. Because the choice between quantity and quality of life is a highly individualistic one, both the patient and his partner should be involved in making decisions about prostate cancer screening.
doi:10.1111/j.1525-1497.2004.30046.x
PMCID: PMC1492196  PMID: 15061743
prostate cancer; medical decision making; primary health care; patient preferences
18.  A Canadian national survey of attitudes and knowledge regarding preventive vaccines 
Background
Vaccines have virtually eliminated many diseases, but public concerns about their safety could undermine future public health initiatives.
Objective
To determine Canadians' attitudes and knowledge about vaccines, particularly in view of increasing public concern about bioterrorism and the possible need for emergency immunizations after weaponized anthrax incidents and the events of September 11, 2001.
Method
A 20-question survey based on well-researched dimensions of vaccine responsiveness was telephone-administered to a random sample of N = 1330 adult Canadians in January, 2002.
Results
1057 (79.5%) completed the survey. Respondents perceived vaccines to be highly effective and demonstrated considerable support for further vaccine research. However, results also indicate a lack of knowledge about vaccines and uncertainty regarding the safety.
Conclusions
Support for vaccines is broad but shallow. While Canadians hold generally positive attitudes about vaccines, support could be undermined by widely publicized adverse events. Better public education is required to maintain support for future public health initiatives.
doi:10.1186/1476-8518-1-3
PMCID: PMC280696  PMID: 14613575
preventive vaccines; attitudes; knowledge; nationwide Canadian survey
19.  Factors associated with the high cost of liver transplantation in adults 
Canadian Journal of Surgery  2002;45(6):425-434.
Objectives
To determine the overall direct cost of liver transplantation in Canadian adults and to identify the factors that are associated with high cost.
Methods
The direct cost of liver transplantation from the perspective of third-party payers was determined in a retrospective analysis of data from hospital charts and databases. A consecutive series of 119 adults who underwent liver transplantation between 1991 and 1992 was followed from the date of listing for transplantation to the second anniversary of the transplant. Patient-specific services during the pre-transplantation, transplantation and post-transplantation phases were compiled and costed. The primary consideration was the impact of complications on the cost of transplantation. Secondary considerations were the impact of age, sex of the patient, diagnosis and severity of liver disease on the total cost.
Results
The overall mean measured cost of liver transplantation was Can$89 066 (range from Can$30 505–Can$690 431). The multivariate logistic regression model for overall costs revealed that severe liver disease (OR = 11.97), cytomegalovirus infection (OR = 6.12), additional operative procedure (OR = 4.22) and biliary complications (OR = 5.00) were associated with an increased likelihood of high cost. The addition of services that were not measured in the present analysis increased the total overall cost to a mean of $121 732 (1998 Canadian dollars, follow-up costs discounted and inflation adjusted).
Interpretation
The factors that were associated with high cost of liver transplantation in Canadian adults were advanced liver disease, postoperative cytomegalovirus infection, the requirement for additional operative procedures and biliary complications.
PMCID: PMC3684657  PMID: 12500917

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