Ron Dewar

Towards using administrative databases to measure population-based indicators of quality of end-of-life care : testing the methodology

This study is concerned with methods to measure population-based indicators of quality end-of-life care. Using a retrospective cohort approach, we assessed the feasibility, validity and reliability of using administrative databases to measure quality indicators of end-of-life care in two Canadian provinces. The study sample consisted of all females who died of breast cancer between 1 January 1998 and 31 December 2002, in Nova Scotia or Ontario, Canada. From an initial list of 19 quality indicators selected from the literature, seven were determined to be fully measurable in both provinces. An additional seven indicators in one province and three in the other province were partially measurable. Tests comparing administrative and chart data show a high level of agreement with inter-rater reliability, confirming consistency in the chart abstraction process. Using administrative data is an efficient, population-based method to monitor quality of care which can compliment other methods, such as qualitative and purposefully collected clinical data.

Risks of Developing Cancer Relative to Living near a Municipal Solid Waste Landfill Site in Montreal, Quebec, Canada

In this study, we sought to determine whether men who lived near the Miron Quarry municipal solid waste landfill site in Montreal, Quebec, Canada, were at higher risk for developing cancer than individuals who lived at more remote locations. Subjects were selected from a previously completed population-based, interview, cancer case-control study of men who lived in metropolitan Montreal. Thirteen sites of cancer (n = 2 928 subjects) and a population-based control group (n = 417) were analyzed. We used the exact street address at the time of diagnosis to classify subjects by geographic zones and distance from the site. We used unconditional logistic regression to estimate odds ratios (ORs) and associated 95% confidence intervals (CIs) for each site of cancer, adjusted for key covariates. In the exposure zone nearest to the site, elevated risks were found for cancers of the pancreas (adjusted OR = 1.4 [95% CI = 0.8, 2.6]); liver (OR = 1.8 [95% CI = 0.8, 4.3]); and prostate (OR = 1.5 [95% CI = 1.0, 2.1]). A high risk was also found for pancreatic cancer (OR = 1.7 [95% CI = 0.9, 3.5]) and the non-Hodgkins lymphomas (OR = 1.5 [95% CI = 0.8, 2.6]) in a subexposure zone approximately downwind from the site. We used distance from the site as another exposure metric, and higher-than-expected risks were found for pancreatic cancer (OR for living within 1.25 km of the site [OR<1.25km] = 2.2 [95% CI = 1.0, 4.6]); liver cancer (OR<1.5km = 2.1 [95% CI = 0.8, 5.3]); kidney cancer (OR<2 km = 1.4 [95% CI = 0.9, 2.3]); and the non-Hodgkins lymphomas (OR<1km = 2.0 [95% CI = 1.0, 4.0]). Data from this study and from a previous investigation at the same site suggest that men who lived near this landfill site may have been-and may continue to be-at excess risk of cancers of the liver, kidney, pancreas, and non-Hodgkins lymphomas.

Population-based trends in referral of the elderly to a comprehensive palliative care programme

F Burge Associate Professor, Department of Family Medicine, Dalhousie University, Halifax, Nova Scotia, G Johnston Associate Professor, School of Health Services Administration, Dalhousie University, Halifax, Nova Scotia and Senior Epidemiologist, Nova Scotia Cancer Registry, B Lawson Research Associate, Department of Family Medicine, Dalhousie University, Halifax, Nova Scotia, R Dewar Biostatistician, Nova Scotia Cancer Registry and I Cummings Associate Professor, Department of Family Medicine, Dalhousie University, Halifax, Nova Scotia and Director, Palliative Care Program, QEII Health Sciences Centre

Comparison of elapsed times from breast cancer detection to first adjuvant therapy in Nova Scotia in 1999/2000 and 2003/04

Background: Waiting times for cancer care continue to be an important issue for Canadians. We evaluated 2 cohorts of breast cancer patients to compare changes in elapsed times to care, to determine the proportion of patients who received their postoperative oncology consultation within the recommended time and to examine elapsed times between date of surgery and start of first adjuvant therapy. Methods: We conducted a retrospective chart review of all women with surgically treated breast cancer who were referred to a provincial cancer centre for adjuvant therapy. The first cohort comprised women referred between Sept. 1, 1999, and Sept. 1, 2000 (n = 342), and the second cohort comprised women referred between Sept. 1, 2003, and Sept. 1, 2004 (n = 295). A general linear model with a stepwise selection was used to identify dominant factors that influenced elapsed times; covariates included cohort period, age at diagnosis, place of residence, disease stage, type of surgery, type of adjuvant therapy, distance to cancer centre, median household income and mean education level. Results: The overall median time from disease detection to the start of first adjuvant therapy for the combined cohorts was 96 days (quartiles 76, 122); this interval was longer for patients in the second cohort (90 v. 102 days, p < 0.001). For the combined cohorts, significantly more patients saw a radiation oncologist within the recommended time from date of surgery than did patients referred to a medical oncologist (82.7% v. 51.7%; p < 0.001). Patients who received adjuvant radiation therapy as their first adjuvant treatment waited longer from the date of definitive surgery to the start of treatment than did patients who received chemotherapy or hormonal treatment (77 v. 48 or 42 days; p < 0.001). Interpretation: The median elapsed time from the detection of breast cancer to the start of first adjuvant therapy was longer in the second cohort (referred in 2003/04) than in the first cohort (referred in 1999/2000). The proportion of patients whose first oncology consultation was within the recommended timeframe varied significantly according to type of oncology specialist, favouring radiation oncology. Despite this difference in access, patients whose first adjuvant therapy was systemic therapy experienced significantly shorter elapsed times from surgery to the start of adjuvant therapy than did patients whose first adjuvant therapy was radiation therapy.

Elapsed time from breast cancer detection to first adjuvant therapy in a Canadian province, 1999–2000

Background: A number of studies have examined time intervals between care steps in breast cancer diagnosis and treatment. The objective of this study was to document the elapsed time from first clinical or mammographic detection of breast abnormality to initiation of first adjuvant therapy in women with invasive breast cancer in Nova Scotia and to examine the effect of age, disease stage and place of residence on these intervals. Methods: All dates were abstracted from patient charts and the Oncology Patient Information System. Eligible women were those with invasive breast cancer detected by Sept. 1, 1999, who were referred to 1 of 2 provincial cancer treatment centres by Sept. 1, 2000. All time intervals were calculated in days, and only patients experiencing both care events defining an interval were included in the analysis of time to event for that interval. We used proportional hazards regression analysis to evaluate the influence of patient age, disease stage and place of residence on times between care events. Results: A total of 776 new diagnoses of breast cancer were reported to the Nova Scotia Cancer Registry over the study period. Of the 776, 467 met the inclusion criteria, and 364 patients were eligible for analysis. The overall median time from clinical or mammographic detection of breast cancer to initiation of first adjuvant therapy was 91 days (interquartile range 72–123 days). Disease stage was the strongest predictor of elapsed time: the median interval from disease detection to initiation of first adjuvant therapy for patients with stage I disease was 118 days, as compared with 85 days for those with stage II disease and 75 days for those with stage III disease (adjusted hazard ratio [HR] 2.1, 95% confidence interval [CI] 1.6–2.8). Patients aged 70 years or more at diagnosis experienced longer elapsed times (median interval 98 days) than did younger patients (93 days for those aged 50–69 years and 82 days for those aged 49 years or less) (adjusted HR 1.6, 95% CI 1.1–2.4). Interpretation: Women aged 70 or more and those with stage I breast cancer experienced longer elapsed times from disease detection to initiation of first adjuvant therapy than did younger women and those with more advanced disease. These findings may have implications for the design of interventions to minimize intervals between steps in breast cancer care and should be validated within the Canadian context. Future investigation exploring the full spectrum of breast cancer care may lead to a more complete understanding of processes and gaps in the current system.

Population-Based Longitudinal Study of Follow-Up Care for Patients With Colorectal Cancer in Nova Scotia

PURPOSE The purpose of this study was to examine colorectal cancer (CRC) follow-up care in Nova Scotia, Canada. More specifically, the objectives were to describe adherence to two elements of follow-up guidelines (colonoscopies and physician visits) and to identify factors associated with receiving at least guideline-recommended care. METHODS All patients with stage II or III CRC undergoing curative-intent surgery in Nova Scotia, Canada, were identified through the provincial cancer registry and anonymously linked to additional administrative health databases. For a 3-year follow-up period, beginning 1 year after the diagnosis date, descriptive statistics were calculated for physician visits and colonoscopies. Factors associated with receiving at least guideline-recommended care were identified using logistic regression. RESULTS Most patients received follow-up care from multiple physician specialties. In year 3, 58.1% of patients received oncologist follow-up care. Guideline adherence for colonoscopies was 52.4%, whereas guideline adherence for physician visits decreased from 41.9% to 25.4%. Receipt of at least guideline-recommended care was inversely associated with age and comorbidity for colonoscopy and inversely associated with age for physician visits. CONCLUSION Receipt of follow-up care from oncologists and primary care physicians, prolonged oncologist care, and receipt of care inconsistent with guideline recommendations suggest there may be potential issues with inefficient use of cancer system resources and integration of guidelines into follow-up care practices in Nova Scotia. Transitioning routine follow-up to primary care could potentially increase guideline adherence by improving access to and continuity of care. CRC may be well suited to targeted knowledge translation strategies to improve guideline adherence.

Premature mortality due to social and material deprivation in Nova Scotia, Canada.

IntroductionInequalities in health attributable to inequalities in society have long been recognized. Typically, those most privileged experience better health, regardless of universal access to health care. Associations between social and material deprivation and mortality from all causes of death´ a measure of population health, have been described for some regions of Canada. This study further examines the link between deprivation and health, focusing on major causes of mortality for both rural and urban populations. In addition, it quantifies the burden of premature mortality attributable to social and material deprivation in a Canadian setting where health care is accessible to all.MethodsThe study included 35,266 premature deaths (1995-2005), grouped into five causes and aggregated over census dissemination areas. Two indices of deprivation (social and material) were derived from six socioeconomic census variables. Premature mortality was modeled as a function of these deprivation indices using Poisson regression.ResultsPremature mortality increased significantly with increasing levels of social and material deprivation. The impact of material deprivation on premature mortality was similar in urban and rural populations, whereas the impact of social deprivation was generally greater in rural populations. There were a doubling in premature mortality for those experiencing a combination of the most extreme levels of material and social deprivation.ConclusionsSocioeconomic deprivation is an important determinant of health equity and affects every segment of the population. Deprivation accounted for 40% of premature deaths. The 4.3% of the study population living in extreme levels of socioeconomic deprivation experienced a twofold increased risk of dying prematurely. Nationally, this inequitable risk could translate into a significant public health burden.