The DOI matches its Crossref record; 13 of the 13 references it cites were found in a registry or an index.
Bias in Treatment Assignment in Controlled Clinical Trials
Abstract
Controlled clinical trials of the treatment of acute myocardial infarction offer a unique opportunity for the study of the potential influence on outcome of bias in treatment assignment. A group of 145 papers was divided into those in which the randomization process was blinded (57 papers), those in which it may have been unblinded (45 papers), and those in which the controls were selected by a nonrandom process (43 papers). At least one prognostic variable was maldistributed (P less than 0.05) in 14.0 per cent of the blinded-randomization studies, in 26.7 per cent of the unblinded-randomization studies, and in 58.1 per cent of the nonrandomized studies. Differences in case-fatality rates between treatment and control groups (P less than 0.05) were found in 8.8 per cent of the blinded-randomization studies, 24.4 per cent of the unblinded-randomization studies, and 58.1 per cent of the nonrandomized studies. These data emphasize the importance of keeping those who recruit patients for clinical trials from suspecting which treatment will be assigned to the patient under consideration.
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In the citing paper
“However, there is evidence that poor reporting of randomisation increases the odds of presenting 'significant' outcomes (Chalmers 1983;Schulz 1995).”
From Psychological therapies for people with borderline personality disorder. (2012) · cites this paper as Chalmers 1983
In the citing paper
“Using a validated method of randomisation helps minimise selection bias and reduce systematic differences in the characteristics of animals allocated to different groups [62–64].”
From Reporting animal research: Explanation and elaboration for the ARRIVE guidelines 2.0 (2020) · cites this paper as [64]
Citations
Cites
Freiman, J. A., Chalmers, T. C., Smith, H., & Kuebler, R. R. (1978) · New England Journal of Medicine · doi:10.1056/nejm197809282991304 · Cited by 1,628
Self-citationA New Design for Randomized Clinical Trials
Zelen, M. (1979) · New England Journal of Medicine · doi:10.1056/nejm197905313002203 · Cited by 1,057
Randomized versus historical controls for clinical trials
Sacks, H., Chalmers, T. C., & Smith, H. (1982) · The American Journal of Medicine · doi:10.1016/0002-9343(82)90815-4 · Cited by 834
Self-citationAssociation of Adrenocorticosteroid Therapy and Peptic-Ulcer Disease
Messer, J., Reitman, D., Sacks, H. S., Smith, H., & Chalmers, T. C. (1983) · New England Journal of Medicine · doi:10.1056/nejm198307073090105 · Cited by 420
Self-citationRothman, K. J. (1978) · New England Journal of Medicine · doi:10.1056/nejm197812142992410 · Cited by 281
Non-Randomized Controls in Cancer Clinical Trials
Gehan, E. A., & Freireich, E. J. (1974) · New England Journal of Medicine · doi:10.1056/nejm197401242900405 · Cited by 276
Allocation of Subjects in Medical Experiments
Weinstein, M. C. (1974) · New England Journal of Medicine · doi:10.1056/nejm197412122912405 · Cited by 189
Are Randomized Trials Appropriate for Evaluating New Operations?
Bonchek, L. I. (1979) · New England Journal of Medicine · doi:10.1056/nejm197907053010110 · Cited by 103
The Role of the Randomized Clinical Trial in the Evaluation of New Operations
Bonchek, L. I. (1982) · Surgical Clinics of North America · doi:10.1016/s0039-6109(16)42793-3 · Cited by 29
Randomized clinical trials in surgery.
Folland, E. D., Hammermeister, K. E., Khuri, S. F., Rahimtoola, S. H., Sethi, G. K., & Souchek, J. (1979) · PubMed · Cited by 22
Research works printed but not linked: 1
- 1981, Milbank Mem Fund Q, 0, 324
Cited by
Sorted by citations
Bias in meta-analysis detected by a simple, graphical test
Egger, M., Smith, G. D., Schneider, M., & Minder, C. (1997) · BMJ · doi:10.1136/bmj.315.7109.629 · Cited by 56,722
Schulz (1995) · doi:10.1001/jama.1995.03520290060030 · Cited by 5,634
SYRCLE’s risk of bias tool for animal studies
Hooijmans, C. R., Rovers, M. M., de Vries, R. B., Leenaars, M., Ritskes-Hoitinga, M., & Langendam, M. W. (2014) · BMC Medical Research Methodology · doi:10.1186/1471-2288-14-43 · Cited by 4,415
Randomized, Controlled Trials, Observational Studies, and the Hierarchy of Research Designs
Concato, J., Shah, N., & Horwitz, R. I. (2000) · New England Journal of Medicine · doi:10.1056/nejm200006223422507 · Cited by 3,563
Evaluating non-randomised intervention studies
Deeks, J., Dinnes, J., D'Amico, R., Sowden, A., Sakarovitch, C., Song, F., Petticrew, M., & Altman, D. (2003) · Health Technology Assessment · doi:10.3310/hta7270 · Cited by 2,907
Metadata
- Authors
- Chalmers, T. C., Celano, P., Sacks, H. S., & Smith, H.
- Affiliations
- Mount Sinai Hospital (US)
- Venue
- New England Journal of Medicine
- Publisher
- Massachusetts Medical Society
- Published
- 1983-12
- Volume
- 309
- Issue
- 22
- Pages
- 1358-1361
- ISSN
- 0028-4793 (ISSN-L)
- 1533-4406
- OpenAlex
- W2030192997
- Cited by
- 864
- References
- 13
- Citations by year
- 2026: 1 · 2025: 3 · 2024: 8 · 2023: 6 · 2022: 10 · 2021: 9 · 2020: 8 · 2019: 14 · 2018: 7 · 2017: 18 · 2016: 15 · 2015: 19 · 2014: 15 · 2013: 18 · 2012: 19
- FWCI
- 13.03
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- New England Journal of Medicine (publishedVersion)
- PubMed (publishedVersion)
- DigitalGeorgetown (Georgetown University Library) (submittedVersion)
- Topics
- Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Clinical Trials
- Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Meta-analysis and systematic reviews
- Physical Sciences › Mathematics › Statistics and Probability › Advanced Causal Inference Techniques
- Keywords
- unblinding, acute myocardial infarction, case fatality, control selection, clinical trial design
- MeSH terms
- Clinical Trials as Topic, Ethics, Medical, Humans, Myocardial Infarction, Outcome and Process Assessment, Health Care, Prognosis, Random Allocation, Research Design, Risk
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