Certain regions adopt an aggressive approach (routine cardiac catheterization and frequent invasive revascularization) to care for acute myocardial infarction (AMI), while other regions adopt a conservative approach (selective use of invasive procedures). Administrative data provide a means to estimate the effects of these variations on patient outcomes, but they are limited by their potential for confounding bias due to unobserved case-mix variation as treatment assignment is not random. This study applied instrumental variables, a methodology that can account for this bias, to estimate the effectiveness of aggressive care in a Canadian patient population. The study used administrative data of hospital admissions and health services for all patients admitted for a first AMI in Quebec in 1988 (n = 8674). Incremental (marginal) mortality up to 4 years after admission was measured using distances to hospitals offering aggressive care as instrumental variables. / Patients living closer to hospitals offering aggressive care were more likely to receive aggressive care than patients living further away (e.g. 26% versus 19%, respectively, received catheterization within 90 days). However, instrumental variable estimation found that aggressive care was not associated with marginal mortality benefits in comparison to conservative care (e.g. adjusted difference at 1 year: 4%; 95% CI: -11% to 20%). / The aggressive approach to post-AMI care is not associated with marginal mortality benefits in Quebec.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.31192 |
| Date | January 2001 |
| Creators | Beck, Christine Ann. |
| Contributors | Pilote, Louise (advisor), Gyorkos, Theresa W. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Epidemiology and Biostatistics.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001804720, proquestno: MQ70382, Theses scanned by UMI/ProQuest. |
Page generated in 0.0021 seconds