Randomized, controlled trials, observational studies, and the hierarchy of research designs.

By J. Concato, N. Shah, R. Horwitz. New England Journal of Medicine, 2000

3,551 citations recorded by the source corpus.

Subfields: Immunology, Infectious Diseases, Statistics and Probability

View Paper: https://www.semanticscholar.org/paper/5ea8cb46aa042073a9aabba3c3303dfbdf8a681c

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Immunology

1. John P. A. Ioannidis
2. David Evans
3. R. Rosenheck

In Infectious Diseases

1. John P. A. Ioannidis
2. David Evans
3. R. Rosenheck

In Statistics and Probability

1. Douglas G. Altman
2. David Moher
3. K. F. Schulz
4. Johannes B Reitsma
5. Matthias Egger
6. Karel G. M. Moons
7. John P. A. Ioannidis
8. Diana Elbourne

Citations in the corpus

• Comparison of evidence of treatment effects in randomized and nonrandomized studies. (2001, background): “On the other hand, recent evaluations have suggested that for selected medical topics, both randomized and nonrandomized studies may yield very similar results.(7,8,13) There is a need to address these issues using empirical data from a large number of diverse medical topics.”
• MSˆ2: Multi-Document Summarization of Medical Studies (2021, background): “clinical trials, cohort studies, observational studies, case studies, and more (Concato et al., 2000).”
• Analysis of observational studies in the presence of treatment selection bias: effects of invasive cardiac management on AMI survival using propensity score and instrumental variable methods. (2007, background): “Randomized clinical trials and observational studies show the greatest similarities under such conditions.(34,35) Observational studies of invasive procedures are more prone to bias because patients who are candidates for surgery often differ in unmeasurable ways from patients who are not.”
• Surgical vs nonoperative treatment for lumbar disk herniation: the Spine Patient Outcomes Research Trial (SPORT) observational cohort. (2006, neutral): “Herniation level§ L2-L3 or L3-L4 32 (6) 24 (13) 56 (8) 32 (7)”
• Medical big data: promise and challenges (2017, background): “In contrast, each randomized controlled trial may have a distinct group of patients according to its specific inclusion and exclusion criteria, and the experimental protocol for therapy may not be representative of clinical practice [27].”
• Hierarchy of evidence: a framework for ranking evidence evaluating healthcare interventions. (2003, result): “Recently, however, comparisons of the results of observational studies and RCTs evaluating the same intervention have questioned this claim (Benson & Hartz, 2000; Concato et al., 2000), and suggest that the findings of observational studies are similar to those produced by RCTs.”
• The Revised CONSORT Statement for Reporting Randomized Trials: Explanation and Elaboration (2001, background): “Indeed, methodologic investigators often (195– 197) but not always (198, 199) detect consistent differences when they compare nonrandomized and randomized studies.”