Deborah J. Cook

Bio: Deborah J. Cook is an academic researcher from McMaster University. The author has contributed to research in topics: Intensive care & Intensive care unit. The author has an hindex of 173, co-authored 907 publications receiving 148928 citations. Previous affiliations of Deborah J. Cook include McMaster University Medical Centre & Queen's University.

Prophylaxis against Upper Gastrointestinal Bleeding in Hospitalized Patients.

Abstract: Preventing Gastrointestinal Bleeding in the Hospital Acid suppression is widely used to lower the risk of gastrointestinal bleeding in critically ill patients, and the practice has spread to patien...

Pulmonary artery catheters: Evolving rates and reasons for use*

Abstract: Objective:Randomized trials have demonstrated risks and failed to establish a clear benefit for the use of the pulmonary artery catheter. We assessed rates of pulmonary artery catheter use in multiple centers over 5 yrs, variables associated with their use, and how these variables changed over time

A systematic review of studies comparing health outcomes in Canada and the United States.

Abstract: Background: Differences in medical care in the United States compared with Canada, including greater reliance on private funding and for-profit delivery, as well as markedly higher expenditures, may result in different health outcomes. Objectives: To systematically review studies comparing health outcomes in the United States and Canada among patients treated for similar underlying medical conditions. Methods: We identified studies comparing health outcomes of patients in Canada and the United States by searching multiple bibliographic databases and resources. We masked study results before determining study eligibility. We abstracted study characteristics, including methodological quality and generalizability. Results: We identified 38 studies comparing populations of patients in Canada and the United States. Studies addressed diverse problems, including cancer, coronary artery disease, chronic medical illnesses and surgical procedures. Of 10 studies that included extensive statistical adjustment and enrolled broad populations, 5 favoured Canada, 2 favoured the United States, and 3 showed equivalent or mixed results. Of 28 studies that failed one of these criteria, 9 favoured Canada, 3 favoured the United States, and 16 showed equivalent or mixed results. Overall, results for mortality favoured Canada (relative risk 0.95, 95% confidence interval 0.92–0.98, p = 0.002) but were very heterogeneous, and we failed to find convincing explanations for this heterogeneity. The only condition in which results consistently favoured one country was end-stage renal disease, in which Canadian patients fared better. Interpretation: Available studies suggest that health outcomes may be superior in patients cared for in Canada versus the United States, but differences are not consistent.

Perioperative fluid therapy with tetrastarch and gelatin in cardiac surgery--a prospective sequential analysis*.

Abstract: Objectives:To determine clinical outcomes of synthetic colloids, tetrastarch, and gelatin, used before and after cardiac surgery.Design:Prospective observational cohort study.Setting:Fifty-bed cardiac ICU.Patients:Six thousand four hundred seventy-eight consecutive patients with cardiopulmonary bypa

Randomized, controlled clinical trials in sepsis: has methodological quality improved over time?

Abstract: Objective: To systematically evaluate the methodological quality of randomized clinical trials and to determine whether randomized clinical trials of sepsis improved in methodological quality over time. Data Sources: Computerized MEDLINE search of articles published in any language from 1966 to 1998 combined with a manual search of bibliographies of published articles and communication with known experts in the field. Study Selection: All randomized clinical trials of sepsis, severe sepsis, and septic shock performed in adults and published as full articles. Data Extraction: Abstracts of all retrieved records were reviewed and the inclusion criteria were applied. All selected articles were classified into (a) trials designed to detect differences in mortality as the primary end point, or (b) trials focusing on surrogate outcome measures (i.e., physiological or biochemical parameters). All retrieved trials were then graded for methodological quality using an objective grading scheme developed specifically for this study. The data selection and extraction process was carried out independently by two of the authors; any disagreement was resolved by discussion. Data Synthesis: Seventy-four randomized clinical trials involving septic patients qualified for inclusion in this study (40 reporting mortality outcomes, 34 reporting other surrogate outcomes). Trials reporting mortality as the primary outcome had significantly higher quality scores compared with trials reporting surrogate outcome measures (29.6 1.0 vs. 24.3 0.8, p .0006). From 1976 to 1998, trial methodology improved significantly over time (an average of 0.36 points per year, p .021). Mortality outcome trials improved an average of 0.58 points per year (p .0011) whereas surrogate outcome trials did not demonstrate an improvement in methodological quality over time (p .249). Conclusion: The methodological limitations identified in this article can help to target further improvement in trial design to enhance the validity of findings from future randomized clinical trials of sepsis. (Crit Care Med 2002; 30:461‐472)

Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement

Abstract: David Moher and colleagues introduce PRISMA, an update of the QUOROM guidelines for reporting systematic reviews and meta-analyses

Preferred reporting items for systematic reviews and meta-analyses: the PRISMA Statement.

Abstract: Systematic reviews and meta-analyses have become increasingly important in health care. Clinicians read them to keep up to date with their field,1,2 and they are often used as a starting point for developing clinical practice guidelines. Granting agencies may require a systematic review to ensure there is justification for further research,3 and some health care journals are moving in this direction.4 As with all research, the value of a systematic review depends on what was done, what was found, and the clarity of reporting. As with other publications, the reporting quality of systematic reviews varies, limiting readers' ability to assess the strengths and weaknesses of those reviews. Several early studies evaluated the quality of review reports. In 1987, Mulrow examined 50 review articles published in 4 leading medical journals in 1985 and 1986 and found that none met all 8 explicit scientific criteria, such as a quality assessment of included studies.5 In 1987, Sacks and colleagues6 evaluated the adequacy of reporting of 83 meta-analyses on 23 characteristics in 6 domains. Reporting was generally poor; between 1 and 14 characteristics were adequately reported (mean = 7.7; standard deviation = 2.7). A 1996 update of this study found little improvement.7 In 1996, to address the suboptimal reporting of meta-analyses, an international group developed a guidance called the QUOROM Statement (QUality Of Reporting Of Meta-analyses), which focused on the reporting of meta-analyses of randomized controlled trials.8 In this article, we summarize a revision of these guidelines, renamed PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses), which have been updated to address several conceptual and practical advances in the science of systematic reviews (Box 1). Box 1 Conceptual issues in the evolution from QUOROM to PRISMA

Measuring inconsistency in meta-analyses

Abstract: Cochrane Reviews have recently started including the quantity I 2 to help readers assess the consistency of the results of studies in meta-analyses. What does this new quantity mean, and why is assessment of heterogeneity so important to clinical practice? Systematic reviews and meta-analyses can provide convincing and reliable evidence relevant to many aspects of medicine and health care.1 Their value is especially clear when the results of the studies they include show clinically important effects of similar magnitude. However, the conclusions are less clear when the included studies have differing results. In an attempt to establish whether studies are consistent, reports of meta-analyses commonly present a statistical test of heterogeneity. The test seeks to determine whether there are genuine differences underlying the results of the studies (heterogeneity), or whether the variation in findings is compatible with chance alone (homogeneity). However, the test is susceptible to the number of trials included in the meta-analysis. We have developed a new quantity, I 2, which we believe gives a better measure of the consistency between trials in a meta-analysis. Assessment of the consistency of effects across studies is an essential part of meta-analysis. Unless we know how consistent the results of studies are, we cannot determine the generalisability of the findings of the meta-analysis. Indeed, several hierarchical systems for grading evidence state that the results of studies must be consistent or homogeneous to obtain the highest grading.2–4 Tests for heterogeneity are commonly used to decide on methods for combining studies and for concluding consistency or inconsistency of findings.5 6 But what does the test achieve in practice, and how should the resulting P values be interpreted? A test for heterogeneity examines the null hypothesis that all studies are evaluating the same effect. The usual test statistic …