Comparison of evidence of treatment effects in randomized and nonrandomized studies.

By John P. A. Ioannidis, Anna-Bettina Haidich, Maroudia Pappa, N. Pantazis, S. Kokori, M. Tektonidou, D. Contopoulos-Ioannidis, Joseph Lau. Journal of the American Medical Association (JAMA), 2001

862 citations recorded by the source corpus.

Subfields: Statistics and Probability

View Paper: https://www.semanticscholar.org/paper/51b5c88bbf52ff11a65bdc4fe573d6c983740891

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Citations in the corpus

Reasons or excuses for avoiding meta-analysis in forest plots (2008, background): “However, the generalised synthesis of both randomised and non-randomised studies on the same topic may offer complementary information.”
Thresholds for statistical and clinical significance in systematic reviews with meta-analytic methods (2014, result): “analyses of trials with low risk of bias are more reliable than results of single large trials [6-11].”
A Call for Examining Replication and Bias in Special Education Research (2014, background): “…randomized and nonrandomized trials, Kunz, Vist, and Oxman (2008) reported that higher effects occurred for non-randomized studies 22 times, whereas randomized studies reported a higher effect in only four comparisons (see also Ioannidis et al., 2001)— likely due to the effects of selection bias.”
2007 Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Health Care Settings (2007, background): “Observational studies remain relevant and have been used to evaluate infection control interventions.(4,5) The quality of studies, consistency of results, and correlation with results from randomized controlled trials, when available, were considered during the literature review and assignment of ev”
Observational studies analyzed like randomized experiments: an application to postmenopausal hormone therapy and coronary heart disease (2008, background): “These ITT estimates are similar to those from the Women’s Health Initiative.”
Evidence-Based Education Policies: Transforming Educational Practice and Research (2002, methodology): “A 1999 review of the research on 24 comprehensive reform models by the American Institutes of Research (AIR) ( Herman, 1999 ) categorized them as having strong evidence of effectiveness; promising, marginal, mixed, weak, or no effects; or no research.”
Contradicted and initially stronger effects in highly cited clinical research. (2005, background): “disagreements between epidemiological studies and randomized trials.(3-5) Prior investigations have focused on a”