John P. A. Ioannidis

305.0k citations
1.1k papers · 189.3k indexed · 79 hit papers · h-index 165
Co-authors
David MoherPeter C GøtzscheCynthia D. MulrowJennifer TetzlaffP.J. DevereauxJos KleijnenMike ClarkeDouglas G. Altman
Topics
Meta-analysis and systematic reviews (316 papers)Health Systems, Economic Evaluations, Quality of Life (188 papers)Statistical Methods in Clinical Trials (112 papers)
Cited by
Statistics, Probability and UncertaintyHealth InformaticsStatistics and Probability
Journals
NatureScienceNew England Journal of Medicine
Partner nations
United StatesGreeceUnited Kingdom

In The Last Decade

John P. A. Ioannidis

1.1k papers receiving 184.3k citations

Hit Papers

The PRISMA Statement for Reporting Systematic Review...1998202620072016200920092009200920055.0k10.0k15.0k20.0k
What are hit papers?

Hit papers significantly outperform the citation benchmark for their cohort. A paper qualifies if it has ≥500 total citations, achieves ≥1.5× the top-1% citation threshold for papers in the same subfield and year (this is the minimum needed to enter the top 1%, not the average within it), or reaches the top citation threshold in at least one of its specific research topics.

  1. The PRISMA Statement for Reporting Systematic Reviews and Meta-Analyses of Studies That Evaluate Health Care Interventions: Explanation and Elaboration
    2009 24.4k citations John P. A. Ioannidis et al. PLoS Medicine profile →
  2. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate healthcare interventions: explanation and elaboration
    2009 14.6k citations John P. A. Ioannidis et al. profile →
  3. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration
    2009 8.8k citations John P. A. Ioannidis et al. profile →
  4. The PRISMA Statement for Reporting Systematic Reviews and Meta-Analyses of Studies That Evaluate Health Care Interventions: Explanation and Elaboration
    2009 8.4k citations John P. A. Ioannidis et al. profile →
  5. Why Most Published Research Findings Are False
    2005 6.0k citations John P. A. Ioannidis PLoS Medicine profile →
  6. The PRISMA Extension Statement for Reporting of Systematic Reviews Incorporating Network Meta-analyses of Health Care Interventions: Checklist and Explanations
    2015 5.7k citations Georgia Salanti, John P. A. Ioannidis et al. profile →
  7. Recommendations for examining and interpreting funnel plot asymmetry in meta-analyses of randomised controlled trials
    2011 5.5k citations John P. A. Ioannidis, Julian P. T. Higgins et al. profile →
  8. Power failure: why small sample size undermines the reliability of neuroscience
    2013 4.9k citations John P. A. Ioannidis et al. profile →
  9. Why Most Published Research Findings Are False
    2005 3.4k citations John P. A. Ioannidis profile →
  10. Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD): Explanation and Elaboration
    2015 3.1k citations John P. A. Ioannidis et al. profile →
  11. Graphical methods and numerical summaries for presenting results from multiple-treatment meta-analysis: an overview and tutorial
    2010 2.8k citations Georgia Salanti, A. E. Ades et al. profile →
  12. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration
    2009 2.3k citations John P. A. Ioannidis et al. profile →
  13. Comparative efficacy and acceptability of 21 antidepressant drugs for the acute treatment of adults with major depressive disorder: a systematic review and network meta-analysis
    2018 2.1k citations Georgia Salanti, Julian P. T. Higgins et al. profile →
  14. Genome-wide association studies for complex traits: consensus, uncertainty and challenges
    2008 1.9k citations John P. A. Ioannidis et al. profile →
  15. A manifesto for reproducible science
    2017 1.7k citations John P. A. Ioannidis et al. profile →
  16. The Hartung-Knapp-Sidik-Jonkman method for random effects meta-analysis is straightforward and considerably outperforms the standard DerSimonian-Laird method
    2014 1.4k citations John P. A. Ioannidis et al. profile →
  17. Plea for routinely presenting prediction intervals in meta-analysis
    2016 1.4k citations John P. A. Ioannidis et al. profile →
  18. Replication validity of genetic association studies
    2001 1.4k citations John P. A. Ioannidis, Despina G. Contopoulos‐Ioannidis et al. profile →
  19. The case of the misleading funnel plot
    2006 1.3k citations John P. A. Ioannidis et al. profile →
  20. Better Reporting of Harms in Randomized Trials: An Extension of the CONSORT Statement
    2004 1.1k citations John P. A. Ioannidis et al. profile →
  21. Systematic Review of the Empirical Evidence of Study Publication Bias and Outcome Reporting Bias
    2008 1.1k citations John P. A. Ioannidis et al. profile →
  22. Uncertainty in heterogeneity estimates in meta-analyses
    2007 977 citations John P. A. Ioannidis, Εvangelos Εvangelou et al. profile →
  23. Why Most Discovered True Associations Are Inflated
    2008 976 citations John P. A. Ioannidis profile →
  24. Increasing value and reducing waste in research design, conduct, and analysis
    2014 960 citations John P. A. Ioannidis et al. profile →
  25. Contradicted and Initially Stronger Effects in Highly Cited Clinical Research
    2005 941 citations John P. A. Ioannidis profile →
  26. Sensitivity of between-study heterogeneity in meta-analysis: proposed metrics and empirical evaluation
    2008 892 citations Εvangelos Εvangelou, John P. A. Ioannidis et al. International Journal of Epidemiology profile →
  27. The Mass Production of Redundant, Misleading, and Conflicted Systematic Reviews and Meta‐analyses
    2016 865 citations John P. A. Ioannidis profile →
  28. Evaluation of networks of randomized trials
    2007 861 citations Georgia Salanti, Julian P. T. Higgins et al. Statistical Methods in Medical Research profile →
  29. Neoadjuvant Versus Adjuvant Systemic Treatment in Breast Cancer: A Meta-Analysis
    2005 847 citations John P. A. Ioannidis et al. profile →
  30. How to increase value and reduce waste when research priorities are set
    2014 843 citations John P. A. Ioannidis et al. profile →
  31. The appropriateness of asymmetry tests for publication bias in meta-analyses: a large survey
    2007 843 citations John P. A. Ioannidis et al. profile →
  32. Systematic meta-analyses and field synopsis of genetic association studies in schizophrenia: the SzGene database
    2008 783 citations John P. A. Ioannidis et al. profile →
  33. Influence of Reported Study Design Characteristics on Intervention Effect Estimates From Randomized, Controlled Trials
    2012 768 citations John P. A. Ioannidis et al. profile →
  34. Vitamin D and multiple health outcomes: umbrella review of systematic reviews and meta-analyses of observational studies and randomised trials
    2014 709 citations John P. A. Ioannidis et al. profile →
  35. What does research reproducibility mean?
    2016 681 citations Steven N. Goodman, John P. A. Ioannidis et al. profile →
  36. Reproducibility in Science
    2014 653 citations John P. A. Ioannidis et al. profile →
  37. Comparison of Evidence of Treatment Effects in Randomized and Nonrandomized Studies
    2001 645 citations John P. A. Ioannidis profile →
  38. Artificial intelligence versus clinicians: systematic review of design, reporting standards, and claims of deep learning studies
    2020 641 citations John P. A. Ioannidis et al. profile →
  39. Heterogeneity testing in meta‐analysis of genome searches
    2004 635 citations John P. A. Ioannidis et al. profile →
  40. Can trial sequential monitoring boundaries reduce spurious inferences from meta-analyses?
    2008 625 citations John P. A. Ioannidis et al. International Journal of Epidemiology profile →
  41. Type 2 diabetes and cancer: umbrella review of meta-analyses of observational studies
    2015 602 citations John P. A. Ioannidis et al. profile →
  42. Demystifying trial networks and network meta-analysis
    2013 552 citations John P. A. Ioannidis et al. profile →
  43. Opportunities and challenges in developing risk prediction models with electronic health records data: a systematic review
    2016 548 citations Benjamin A. Goldstein, Ann Marie Návar et al. Journal of the American Medical Informatics Association profile →
  44. An exploratory test for an excess of significant findings
    2007 534 citations John P. A. Ioannidis et al. profile →
  45. Summing up evidence: one answer is not always enough
    1998 520 citations John P. A. Ioannidis et al. profile →
  46. Controlling high bandwidth aggregates in the network
    2002 516 citations John P. A. Ioannidis et al. profile →
  47. Interpretation of tests of heterogeneity and bias in meta‐analysis
    2008 511 citations John P. A. Ioannidis profile →
  48. Environmental risk factors and multiple sclerosis: an umbrella review of systematic reviews and meta-analyses
    2015 501 citations Εvangelos Εvangelou, John P. A. Ioannidis et al. profile →
  49. Integration of evidence from multiple meta-analyses: a primer on umbrella reviews, treatment networks and multiple treatments meta-analyses
    2009 489 citations John P. A. Ioannidis profile →
  50. How to Make More Published Research True
    2014 457 citations John P. A. Ioannidis PLoS Medicine profile →
  51. Comparative effectiveness of exercise and drug interventions on mortality outcomes: metaepidemiological study
    2013 441 citations John P. A. Ioannidis et al. profile →
  52. Empirical assessment of published effect sizes and power in the recent cognitive neuroscience and psychology literature
    2017 423 citations John P. A. Ioannidis et al. profile →
  53. Effect of Low-Fat vs Low-Carbohydrate Diet on 12-Month Weight Loss in Overweight Adults and the Association With Genotype Pattern or Insulin Secretion
    2018 411 citations John P. A. Ioannidis et al. profile →
  54. The Proposal to Lower P Value Thresholds to .005
    2018 404 citations John P. A. Ioannidis profile →
  55. PRISMA harms checklist: improving harms reporting in systematic reviews
    2016 391 citations John P. A. Ioannidis et al. profile →
  56. Implementing Pushback: Router-Based Defense Against DDoS Attacks
    2002 384 citations John P. A. Ioannidis et al. profile →
  57. The Power of Bias in Economics Research
    2017 383 citations John P. A. Ioannidis et al. profile →
  58. What causes psychosis? An umbrella review of risk and protective factors
    2018 383 citations Joaquim Raduà, John P. A. Ioannidis et al. profile →
  59. Meta-analysis methods for genome-wide association studies and beyond
    2013 374 citations Εvangelos Εvangelou, John P. A. Ioannidis profile →
  60. Standard 6: Age Groups for Pediatric Trials
    2012 365 citations Despina G. Contopoulos‐Ioannidis, John P. A. Ioannidis et al. PEDIATRICS profile →
  61. Development of the Instrument to assess the Credibility of Effect Modification Analyses (ICEMAN) in randomized controlled trials and meta-analyses
    2020 356 citations John P. A. Ioannidis et al. profile →
  62. Why Most Clinical Research Is Not Useful
    2016 342 citations John P. A. Ioannidis PLoS Medicine profile →
  63. Evidence Relating Health Care Provider Burnout and Quality of Care
    2019 325 citations John P. A. Ioannidis et al. profile →
  64. Publication and other reporting biases in cognitive sciences: detection, prevalence, and prevention
    2014 321 citations John P. A. Ioannidis, Paolo Fusar‐Poli et al. profile →
  65. Environmental risk factors and Parkinson's disease: An umbrella review of meta-analyses
    2015 313 citations Εvangelos Εvangelou, John P. A. Ioannidis et al. profile →
  66. Preventive psychiatry: a blueprint for improving the mental health of young people
    2021 259 citations Paolo Fusar‐Poli, John P. A. Ioannidis et al. profile →
  67. Assessing scientists for hiring, promotion, and tenure
    2018 232 citations John P. A. Ioannidis, Steven N. Goodman et al. profile →
  68. The efficacy of psychotherapies and pharmacotherapies for mental disorders in adults: an umbrella review and meta‐analytic evaluation of recent meta‐analyses
    2022 230 citations John P. A. Ioannidis et al. profile →
  69. What Other Countries Can Learn From Italy During the COVID-19 Pandemic
    2020 227 citations John P. A. Ioannidis et al. profile →
  70. The Predictive Approaches to Treatment effect Heterogeneity (PATH) Statement
    2019 220 citations Steven N. Goodman, John P. A. Ioannidis et al. profile →
  71. Evolution of Reporting P Values in the Biomedical Literature, 1990-2015
    2016 217 citations Joshua D. Wallach, John P. A. Ioannidis et al. profile →
  72. The Challenge of Reforming Nutritional Epidemiologic Research
    2018 202 citations John P. A. Ioannidis profile →
  73. Recalibrating the Use of Race in Medical Research
    2021 167 citations John P. A. Ioannidis et al. profile →
  74. Conducting umbrella reviews
    2022 141 citations John P. A. Ioannidis et al. profile →
  75. SARS-CoV-2 reinfections: Overview of efficacy and duration of natural and hybrid immunity
    2022 132 citations Stefan Pilz, Verena Theiler‐Schwetz et al. profile →
  76. Gender-related variables for health research
    2021 128 citations John P. A. Ioannidis et al. profile →
  77. CONSORT Harms 2022 statement, explanation, and elaboration: updated guideline for the reporting of harms in randomised trials
    2023 111 citations John P. A. Ioannidis et al. profile →
  78. Guidance to best tools and practices for systematic reviews
    2023 62 citations John P. A. Ioannidis et al. profile →
  79. The present and future of peer review: Ideas, interventions, and evidence
    2025 15 citations John P. A. Ioannidis et al. Proceedings of the National Academy of Sciences profile →

Peers

John P. A. Ioannidis
Comparison fields: 5 of 240
  • Surgery 25.9k
  • Public Health, Environmental and Occupational Health 20.6k
  • Statistics, Probability and Uncertainty 18.7k
  • Epidemiology 17.9k
  • Pulmonary and Respiratory Medicine 16.1k
Replace Peter C Gøtzsche with:
Peter C Gøtzsche Denmark
Matthias Egger Switzerland
Julian P. T. Higgins United Kingdom
Jennifer Tetzlaff Canada
Kenneth F. Schulz United States
David Moher Canada
Gordon Guyatt Canada
Douglas G. Altman United Kingdom
Mike Clarke United Kingdom
Alessandro Liberati Italy
John P. A. Ioannidis relative to Peter C Gøtzsche Denmark Peter C Gøtzsche's profile →
Citations per field
00.5×1.5×2.0×
Peter C Gøtzsche · 1×
Citations per year

Countries citing papers authored by John P. A. Ioannidis

Since Specialization
Citations

This map shows the geographic impact of John P. A. Ioannidis's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by John P. A. Ioannidis with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites John P. A. Ioannidis more than expected).

Fields of papers citing papers by John P. A. Ioannidis

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by John P. A. Ioannidis. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by John P. A. Ioannidis. The network helps show where John P. A. Ioannidis may publish in the future.

Co-authorship network of co-authors of John P. A. Ioannidis

This figure shows the co-authorship network connecting the top 25 collaborators of John P. A. Ioannidis. A scholar is included among the top collaborators of John P. A. Ioannidis based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with John P. A. Ioannidis. John P. A. Ioannidis is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
#WorkIndexed citations
1
Provenance and Funding of Extremely Cited Biomedical Articles Published Between 2003 and 2024
2025 ·JAMA Health Forum ·John P. A. Ioannidis
0
2
Leading researchers in the leadership of leading research universities: Meta-research analysis
2024 ·Research Policy ·John P. A. Ioannidis
1
3
Variability in excess deaths across countries with different vulnerability during 2020–2023
2023 ·Proceedings of the National Academy of Sciences ·John P. A. Ioannidis,Francesco Zonta,Michael Levitt
11
4
Transparency in Infectious Disease Research: Meta-research Survey of Specialty Journals
2023 ·The Journal of Infectious Diseases ·(unknown),Despina G. Contopoulos‐Ioannidis,John P. A. Ioannidis
2
5
Impact of major awards on the subsequent work of their recipients
2023 ·Royal Society Open Science ·(unknown),(unknown),John P. A. Ioannidis
1
6
Post-publication critique at top-ranked journals across scientific disciplines: a cross-sectional assessment of policies and practice
2022 ·Royal Society Open Science ·Tom E Hardwicke,Robert T. Thibault,Jessica Elizabeth Kosie,Loukia Tzavella,Theiss Bendixen,(unknown),(unknown),John P. A. Ioannidis
21
7
Assessing mandatory stay‐at‐home and business closure effects on the spread of COVID‐19
2021 ·European Journal of Clinical Investigation ·Eran Bendavid,(unknown),Jay Bhattacharya,John P. A. Ioannidis
127
8
SARS‐CoV‐2 re‐infection risk in Austria
2021 ·European Journal of Clinical Investigation ·Stefan Pilz,(unknown),John P. A. Ioannidis,Lukas Richter,Verena Theiler‐Schwetz,Christian Trummer,Robert Krause,Franz Allerberger
107
9
The rapid, massive growth of COVID-19 authors in the scientific literature
2021 ·Royal Society Open Science ·John P. A. Ioannidis,Maia Salholz‐Hillel,Kevin W. Boyack,Jeroen Baas
58
10
Estimating the Prevalence of Transparency and Reproducibility-Related Research Practices in Psychology (2014–2017)
2021 ·Perspectives on Psychological Science ·Tom E Hardwicke,Robert T. Thibault,Jessica Elizabeth Kosie,Joshua D. Wallach,Mallory C. Kidwell,John P. A. Ioannidis
94
11
COVID-19 antibody seroprevalence in Santa Clara County, California
2021 ·International Journal of Epidemiology ·Eran Bendavid,Bianca Mulaney,Neeraj Sood,Soleil Shah,Rebecca Bromley-Dulfano,Cara Lai,(unknown),(unknown),(unknown),(unknown),Thomas C Kupiec,Daniel Eichner,Ribhav Gupta,John P. A. Ioannidis,Jay Bhattacharya
177
12
Calibrating the Scientific Ecosystem Through Meta-Research
2019 ·Annual Review of Statistics and Its Application ·Tom E Hardwicke,Stylianos Serghiou,Perrine Janiaud,Valentin Danchev,Sophia Crüwell,Steven N. Goodman,John P. A. Ioannidis
56
13
Meta-analysis of Voxel-Based Neuroimaging Studies using Seed-based d Mapping with Permutation of Subject Images (SDM-PSI)
2019 ·Journal of Visualized Experiments ·Anton Albajes‐Eizagirre,Aleix Solanes,Miquel À. Fullana,John P. A. Ioannidis,Paolo Fusar‐Poli,Carla Torrent,Brisa Solé,Caterina del Mar Bonnín,Eduard Vieta,David Mataix‐Cols,Joaquim Raduà
39
14
Opportunities and challenges in developing risk prediction models with electronic health records data: a systematic reviewbreakdown →
2016 ·Journal of the American Medical Informatics Association ·Benjamin A. Goldstein,Ann Marie Návar,Michael Pencina,John P. A. Ioannidis
548
15
The Cancer Epidemiology Descriptive Cohort Database: A Tool to Support Population-Based Interdisciplinary Research
2016 ·Cancer Epidemiology Biomarkers & Prevention ·Amy E. Kennedy,Muin J. Khoury,John P. A. Ioannidis,Michelle Brotzman,Amy Miller,(unknown),Gabriel Y. Lai,Scott D. Rogers,Chinonye Harvey,Joanne W. Elena,Daniela Seminara
1
16
Why Most Clinical Research Is Not Usefulbreakdown →
2016 ·PLoS Medicine ·John P. A. Ioannidis
342
17
Narrow band imaging to differentiate neoplastic and non-neoplastic colorectal polyps in real time: a meta-analysis of diagnostic operating characteristics
2013 ·Gut ·Sarah McGill,Εvangelos Εvangelou,John P. A. Ioannidis,Roy Soetikno,Tonya Kaltenbach
118
18
Collaborative Cancer Epidemiology in the 21st Century: The Model of Cancer Consortia
2013 ·Cancer Epidemiology Biomarkers & Prevention ·(unknown),John P. A. Ioannidis,(unknown),Eric DeRycke,Scott D. Rogers,Muin J. Khoury,Daniela Seminara
13
19
Pediatric Versus Adult Drug Trials for Conditions With High Pediatric Disease Burden
2012 ·PEDIATRICS ·Florence T. Bourgeois,Srinivas Murthy,(unknown),Karen L. Olson,John P. A. Ioannidis,Kenneth D. Mandl
99
20
Evaluation of networks of randomized trialsbreakdown →
2007 ·Statistical Methods in Medical Research ·Georgia Salanti,Julian P. T. Higgins,A. E. Ades,John P. A. Ioannidis
861

About John P. A. Ioannidis

John P. A. Ioannidis is a scholar working on Statistics, Probability and Uncertainty, Statistics and Probability and Health Informatics, having authored 1.1k papers that have together received 189.3k indexed citations. Recurring topics across this work include Meta-analysis and systematic reviews (316 papers), Health Systems, Economic Evaluations, Quality of Life (188 papers) and Statistical Methods in Clinical Trials (112 papers). The work is most often cited by research in Statistics, Probability and Uncertainty (18.7k citations), Health Informatics (1.9k citations) and Statistics and Probability (6.7k citations). John P. A. Ioannidis has collaborated with scholars based in United States, Greece and United Kingdom. Frequent co-authors include David Moher, Peter C Gøtzsche, Cynthia D. Mulrow, Jennifer Tetzlaff, P.J. Devereaux, Jos Kleijnen, Mike Clarke, Douglas G. Altman, Alessandro Liberati and Georgia Salanti. Their work appears in journals such as Nature, Science and New England Journal of Medicine.

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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