John P. A. Ioannidis

Large-scale analysis of association between GDF5 and FRZB variants and osteoarthritis of the hip, knee, and hand (2009)

Chapman, Kay, Meulenbelt, Ingrid, Karassa, Fotini B, Loughlin, John, Carr, Andrew, ...

OBJECTIVE: GDF5 and FRZB have been proposed as genetic loci conferring susceptibility to osteoarthritis (OA); however, the results of several studies investigating the association of OA with the...

Underlying Genetic Models of Inheritance in Established Type 2 Diabetes Associations (2009)

Salanti, Georgia, Southam, Lorraine, Altshuler, David, Ardlie, Kristin, Barroso, Inês, Boehnke, Michael, ...

For most associations of common single nucleotide polymorphisms (SNPs) with common diseases, the genetic model of inheritance is unknown. The authors extended and applied a Bayesian meta-analysis...

Genome-Wide Association Studies, Field Synopses, and the Development of the Knowledge Base on Genetic Variation and Human Diseases (2009)

Khoury, Muin J., Bertram, Lars, Boffetta, Paolo, Butterworth, Adam S., Chanock, Stephen J., Dolan, Siobhan M., ...

Genome-wide association studies (GWAS) have led to a rapid increase in available data on common genetic variants and phenotypes and numerous discoveries of new loci associated with susceptibility to...

Can trial sequential monitoring boundaries reduce spurious inferences from meta-analyses? (2009)

Thorlund, Kristian, Devereaux, P J, Wetterslev, Jørn, Guyatt, Gordon, Ioannidis, John P A, Thabane, Lehana, ...

Background Results from apparently conclusive meta-analyses may be false. A limited number of events from a few small trials and the associated random error may be under-recognized sources of...

A Field Synopsis on Low-Penetrance Variants in DNA Repair Genes and Cancer Susceptibility (2009)

Vineis, Paolo, Manuguerra, Maurizio, Kavvoura, Fotini K., Guarrera, Simonetta, Allione, Alessandra, Rosa, Fabio, ...

Background Several genes encoding for DNA repair molecules implicated in maintaining genomic integrity have been proposed as cancer-susceptibility genes. Although efforts have been made to create...

Discovery Properties of Genome-wide Association Signals From Cumulatively Combined Data Sets (2009)

Pereira, Tiago V., Patsopoulos, Nikolaos A., Salanti, Georgia, Ioannidis, John P. A.

Genetic effects for common variants affecting complex disease risk are subtle. Single genome-wide association (GWA) studies are typically underpowered to detect these effects, and combination of...

Measuring co-authorship and networking-adjusted scientific impact (2008)

Ioannidis, John P. A.

Appraisal of the scientific impact of researchers, teams and institutions with productivity and citation metrics has major repercussions. Funding and promotion of individuals and survival of teams...

Large-scale analysis of association between polymorphisms in the transfonning growth factor beta 1 gene (TGFB1) and osteoporosis: The GENOMOS study (2008)

Uitterlinden, Andre G, Ralston, Stuart H, Trikalinos, Thomas A, Balcells, Susanne, Brandi, Maria Luisa, ...

Introduction: The TGFBI gene which encodes transforming growth factor beta 1, is a strong candidate for susceptibility to osteoporosis and several studies have reported associations between bone...

Large-scale analysis of association between LRP5 and LRP6 variants and osteoporosis (2008)

Trikalinos, Thomas A, Ralston, Stuart H, Balcells, Susana, Brandi, Maria Luisa, Brixen, Kim, ...

Context Mutations in the low- density lipoprotein receptor - related protein 5 ( LRP5) gene cause rare syndromes characterized by altered bone mineral density ( BMD). More common LRP5 variants may...

Multiple-Treatments Meta-analysis of Chemotherapy and Targeted Therapies in Advanced Breast Cancer (2008)

Mauri, Davide, Polyzos, Nikolaos P., Salanti, Georgia, Pavlidis, Nicholas, Ioannidis, John P. A.

Background Many systemic nonhormonal regimens have been evaluated across several hundreds of randomized trials in advanced breast cancer. We aimed to quantify the relative merits of these regimens in...

18F-Fluorodeoxyglucose Positron Emission Tomography to Evaluate Cervical Node Metastases in Patients With Head and Neck Squamous Cell Carcinoma: A Meta-analysis (2008)

Kyzas, Panayiotis A., Evangelou, Evangelos, Denaxa-Kyza, Despina, Ioannidis, John P. A.

Background Positron emission tomography using 18F-fluorodeoxyglucose (18F-FDG PET) has been proposed to enhance preoperative assessment of cervical lymph node status in patients with head and neck...

Expectations and challenges stemming from genome-wide association studies (2008)

Vineis, Paolo, Brennan, Paul, Canzian, Federico, Ioannidis, John P. A., Matullo, Giuseppe, Ritchie, Marylyn, ...

There are considerable expectations about the ability of genome-wide association (GWA) studies to make exciting discoveries about the role of genes in common diseases. GWA studies may allow...

Effect of Formal Statistical Significance on the Credibility of Observational Associations (2008)

Ioannidis, John P. A.

The author evaluated the implications of nominal statistical significance for changing the credibility of null versus alternative hypotheses across a large number of observational associations for...

Genetic Effects versus Bias for Candidate Polymorphisms in Myocardial Infarction: Case Study and Overview of Large-Scale Evidence (2007)

Ntzani, Evangelia E., Rizos, Evangelos C., Ioannidis, John P. A.

Several genetic polymorphisms have been proposed to be associated with myocardial infarction (MI). The authors examined the evidence and biases underlying such associations using a case-study...

Meta-Analysis of Genome-Wide Scans Provides Evidence for Sex- and Site-Specific Regulation of Bone Mass (2007)

Ioannidis, John P. A., Ng, Mandy Y., Sham, Pak C., Zintzaras, Elias, Lewis, Cathryn M., Deng, Hong-Wen, ...

Several genome-wide scans have been performed to detect loci that regulate BMD, but these have yielded inconsistent results, with limited replication of linkage peaks in different studies. In an...

Meta-Analysis of Genome-Wide Scans Provides Evidence for Sex- and Site-Specific Regulation of Bone Mass (2007)

Ioannidis, John P. A., Ng, Mandy Y., Sham, Pak C., Zintzaras, Elias, Lewis, Cathryn M., Deng, Hong-Wen, ...

Several genome-wide scans have been performed to detect loci that regulate BMD, but these have yielded inconsistent results, with limited replication of linkage peaks in different studies. In an...

Quality of Reporting of Cancer Prognostic Marker Studies: Association With Reported Prognostic Effect (2007)

Kyzas, Panayiotis A., Denaxa-Kyza, Despina, Ioannidis, John P. A.

Background Issues of reported study quality have not been addressed empirically with large-scale data in the cancer prognostic literature. Methods Eight quality measures pertaining to study design...

Genetic Effects versus Bias for Candidate Polymorphisms in Myocardial Infarction: Case Study and Overview of Large-Scale Evidence (2007)

Ntzani, Evangelia E., Rizos, Evangelos C., Ioannidis, John P. A.

Several genetic polymorphisms have been proposed to be associated with myocardial infarction (MI). The authors examined the evidence and biases underlying such associations using a case-study...

Survival Benefits With Diverse Chemotherapy Regimens for Ovarian Cancer: Meta-analysis of Multiple Treatments (2006)

Kyrgiou, Maria, Salanti, Georgia, Pavlidis, Nicholas, Paraskevaidis, Evangelos, Ioannidis, John P. A.

Background: Numerous randomized trials have compared different chemotherapy regimens in women with ovarian cancer. Although ovarian cancer survival has improved in recent years, the magnitude of...

Large-scale evidence for the effect of the COLIA1 Sp1 polymorphism on osteoporosis outcomes: The GENOMOS study (2006)

Uitterlinden, Andre G, Brandi, Maria Luisa, Balcells, Susana, Langdahl, Bente L, Lips, Paul, ...

Background Osteoporosis and fracture risk are considered to be under genetic control. Extensive work is being performed to identify the exact genetic variants that determine this risk. Previous work...

Lack of replication of thirteen single-nucleotide polymorphisms implicated in Parkinson's disease: a large-scale international study (2006)

Elbaz, Alexis, Nelson, Lorene M., Payami, Haydeh, Ioannidis, John P.A., Fiske, Brian K., Annesi, Grazia, ...

Background A genome-wide association study identified 13 single-nucleotide polymorphisms (SNPs) significantly associated with Parkinson's disease. Small-scale replication studies were largely...

Lack of replication of thirteen single-nucleotide polymorphisms implicated in Parkinson's disease: a large-scale international study (2006)

Elbaz, Alexis, Nelson, Lorene M., Payami, Haydeh, Ioannidis, John P.A., Fiske, Brian K., Annesi, Grazia, ...

Background A genome-wide association study identified 13 single-nucleotide polymorphisms (SNPs) significantly associated with Parkinson's disease. Small-scale replication studies were largely...

Lack of replication of thirteen single-nucleotide polymorphisms implicated in Parkinson's disease: a large-scale international study (2006)

Elbaz, Alexis, Nelson, Lorene M., Payami, Haydeh, Ioannidis, John P.A., Fiske, Brian K., Annesi, Grazia, ...

Background A genome-wide association study identified 13 single-nucleotide polymorphisms (SNPs) significantly associated with Parkinson's disease. Small-scale replication studies were largely...

Implications of Small Effect Sizes of Individual Genetic Variants on the Design and Interpretation of Genetic Association Studies of Complex Diseases (2006)

Ioannidis, John P. A., Trikalinos, Thomas A., Khoury, Muin J.

Accumulated evidence from searching for candidate gene-disease associations of complex diseases can offer some insights as the field moves toward discovery-oriented approaches with massive...

Impact of Violations and Deviations in Hardy-Weinberg Equilibrium on Postulated Gene-Disease Associations (2006)

Trikalinos, Thomas A., Salanti, Georgia, Khoury, Muin J., Ioannidis, John P. A.

The authors evaluated whether statistically significant violations of Hardy-Weinberg equilibrium (HWE) or the magnitude of deviations from HWE may contribute to the problem of replicating postulated...

Survival With Aromatase Inhibitors and Inactivators Versus Standard Hormonal Therapy in Advanced Breast Cancer: Meta-analysis (2006)

Mauri, Davide, Pavlidis, Nicholas, Polyzos, Nikolaos P., Ioannidis, John P. A.

Background: Aromatase inhibitors and inactivators have been extensively tested in patients with advanced breast cancer, but it is unclear whether they offer any survival benefits compared with...

A Network of Investigator Networks in Human Genome Epidemiology (2005)

Ioannidis, John P. A., Bernstein, Jonine, Boffetta, Paolo, Danesh, John, Dolan, Siobhan, Hartge, Patricia, ...

The task of identifying genetic determinants for complex, multigenetic diseases is hampered by small studies, publication and reporting biases, and lack of common standards worldwide. The authors...

Selective Reporting Biases in Cancer Prognostic Factor Studies (2005)

Kyzas, Panayiotis A., Loizou, Konstantinos T., Ioannidis, John P. A.

Background: Nonreported and selectively reported information and the use of different definitions may introduce biases in the literature of prognostic factors. We probed these biases in a...

CTLA-4 Gene Polymorphisms and Susceptibility to Type 1 Diabetes Mellitus: A HuGE Review and Meta-Analysis (2005)

Kavvoura, Fotini K., Ioannidis, John P. A.

The authors performed a meta-analysis of 33 studies examining the association of type 1 diabetes mellitus with polymorphisms in the cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) gene,...

Neoadjuvant Versus Adjuvant Systemic Treatment in Breast Cancer: A Meta-Analysis (2005)

Mauri, Davide, Pavlidis, Nicholas, Ioannidis, John P. A.

Background: Interest in the use of preoperative systemic treatment in the management of breast cancer has increased because such neoadjuvant therapy appears to reduce the extent of local surgery...

HEGESMA: genome search meta-analysis and heterogeneity testing (2005)

Zintzaras, Elias, Ioannidis, John P. A.

Summary: Heterogeneity and genome search meta-analysis (HEGESMA) is a comprehensive software for performing genome scan meta-analysis, a quantitative method to identify genetic regions (bins) with...

HEGESMA: genome search meta-analysis and heterogeneity testing (2005)

Zintzaras, Elias, Ioannidis, John P. A.

Summary: HEGESMA is a comprehensive software for performing genome scan meta-analysis, a quantitative method to identify genetic regions (bins) with consistently increased linkage score across...

A Network of Investigator Networks in Human Genome Epidemiology (2005)

Ioannidis, John P. A., Bernstein, Jonine, Boffetta, Paolo, Danesh, John, Dolan, Siobhan, Hartge, Patricia, ...

The task of identifying genetic determinants for complex, multigenetic diseases is hampered by small studies, publication and reporting biases, and lack of common standards worldwide. The authors...

A Network of Investigator Networks in Human Genome Epidemiology (2005)

Ioannidis, John P. A., Bernstein, Jonine, Boffetta, Paolo, Danesh, John, Dolan, Siobhan, Hartge, Patricia, ...

The task of identifying genetic determinants for complex, multigenetic diseases is hampered by small studies, publication and reporting biases, and lack of common standards worldwide. The authors...

UCHL1 Is a Parkinson's Disease Susceptibility Gene (2004)

Maraganore, Demetrius M., Lesnick, Timothy G., Elbaz, Alexis, Chartier-Harlin, Marie-Christine, Gasser, Thomas, Kruger, Rejko, ...

The reported inverse association between the S18Y variant of the ubiquitin carboxy-terminal hydrolase L1 (UCHL1) gene and Parkinson's disease (PD) has strong biological plausibility. If confirmed,...

UCHL1 Is a Parkinson's Disease Susceptibility Gene (2004)

Maraganore, Demetrius M., Lesnick, Timothy G., Elbaz, Alexis, Chartier-Harlin, Marie-Christine, Gasser, Thomas, Kruger, Rejko, ...

The reported inverse association between the S18Y variant of the ubiquitin carboxy-terminal hydrolase L1 (UCHL1) gene and Parkinson's disease (PD) has strong biological plausibility. If confirmed,...

Meta-Analysis of the Association of the Cathepsin D Ala224Val Gene Polymorphism with the Risk of Alzheimer's Disease: A HuGE Gene-Disease Association Review (2004)

Ntais, Christos, Polycarpou, Anastasia, Ioannidis, John P. A.

A C-to-T polymorphism in exon 2 of the cathepsin D gene encoding cathepsin D (CTSD) has been implicated as a risk factor for Alzheimer’s disease. The authors performed a meta-analysis of 14 studies...

Evidence Report on the Treatment of Pain in Cancer Patients (2004)

Carr, Daniel B., Goudas, Leonidas C., Balk, Ethan M., Bloch, Rina, Ioannidis, John P. A., Lau, Joseph

Pain associated with cancer is of widespread concern. We conducted a systematic review to evaluate the best available evidence on the efficacy of treatments of cancer-related pain. The sources used...

Evaluation of Cluster Randomized Controlled Trials in Sub-Saharan Africa (2003)

Isaakidis, Petros, Ioannidis, John P. A.

Cluster randomized controlled trials (CRCTs) are attractive in settings in which individual randomization is difficult or impossible. This issue is common when studying several health problems in...

Modelling of escalating outpatient antibiotic expenditures (2003)

Zintzaras, Elias, Ioannidis, John P. A.

Objectives: To model the relative role of old and newly introduced antibiotics in shaping increased antibiotic use. Methods: Grouped data covering nationwide consumption and expenditure for...

Modelling of escalating outpatient antibiotic expenditures (2003)

Zintzaras, Elias, Ioannidis, John P. A.

Objectives: To model the relative role of old and newly introduced antibiotics in shaping increased antibiotic use. Methods: Grouped data covering nationwide consumption and expenditure for...

Modelling of escalating outpatient antibiotic expenditures (2003)

Zintzaras, Elias, Ioannidis, John P. A.

Objectives: To model the relative role of old and newly introduced antibiotics in shaping increased antibiotic use. Methods: Grouped data covering nationwide consumption and expenditure for...

Effect of Early Patient Enrollment on the Time to Completion and Publication of Randomized Controlled Trials (2001)

Haidich, Anna-Bettina, Ioannidis, John P. A.

The authors evaluated whether early enrollment affects the significance of the results and the time to completion and publication of randomized controlled trials. Seventy-seven efficacy randomized...

Meta-analysis of randomized controlled trials on the comparative efficacy and safety of azithromycin against other antibiotics for upper respiratory tract infections (2001)

Ioannidis, John P.A., Contopoulos-Ioannidis, Despina G., Chew, Priscilla, Lau, Joseph

We carried out a meta-analysis of randomized controlled trials comparing 3–5 days of azithromycin with other antibiotics that are typically given in longer courses for the treatment of upper...

Meta-analysis of randomized controlled trials on the comparative efficacy and safety of azithromycin against other antibiotics for lower respiratory tract infections (2001)

Contopoulos-Ioannidis, Despina G., Ioannidis, John P. A., Chew, Priscilla, Lau, Joseph

We carried out a meta-analysis of randomized controlled trials of azithromycin compared with other antibiotics in the treatment of lower respiratory tract infections, including acute bronchitis (five...

Use of Neural Networks to Model Complex Immunogenetic Associations of Disease: Human Leukocyte Antigen Impact on the Progression of Human Immunodeficiency Virus Infection (1998)

Ioannidis, John P. A., McQueen, Philip G., Goedert, James J., Kaslow, Richard A.

Complex immunogenetic associations of disease involving a learge number of gene products are difficult to evaluate with traditional statistical methods and may require complex modeling. The authors...

Evolution of treatment effects over time: Empirical insight from recursive cumulative metaanalyses

Ioannidis, John P. A., Lau, Joseph

Evidence on how much medical interventions work may change over time. It is important to determine what fluctuations in the treatment effect reported by randomized trials and their metaanalyses may...

Are amoxycillin and folate inhibitors as effective as other antibiotics for acute sinusitis? A meta-analysis

De Ferranti, Sarah D, Ioannidis, John P A, Lau, Joseph, Anninger, William V, Barza, Michael

Objectives: To examine whether antibiotics are indicated in treating uncomplicated acute sinusitis and, if so, whether newer and more expensive antibiotics with broad spectra of antimicrobial...

The Decameron of poor research

Berger, Vance W, Ioannidis, John P A

Most gracious readers, two boring researchers present a series of pitiful tales—covert and overt fraud, petty misdeeds, and misconceptions by honest and not so honest researchers, professors,...

Why Most Published Research Findings Are False

Ioannidis, John P. A.

Published research findings are sometimes refuted by subsequent evidence, says Ioannidis, with ensuing confusion and disappointment.

Local Literature Bias in Genetic Epidemiology: An Empirical Evaluation of the Chinese Literature

Pan, Zhenglun, Trikalinos, Thomas A, Kavvoura, Fotini K, Lau, Joseph, Ioannidis, John P.A

Using the chinese literature as an example, John Ioannidis and colleagues show that selective reporting and language biases occur frequently in human genome epidemiology

Large-Scale Evidence for the Effect of the COLIA1 Sp1 Polymorphism on Osteoporosis Outcomes: The GENOMOS Study

Ralston, Stuart H, Uitterlinden, André G, Brandi, Maria Luisa, Balcells, Susana, Langdahl, Bente L, Lips, Paul, ...

A large collaborative European study finds only weak links between a much studied potential genetic risk factor and bone mineral density or fracture risk.

Origin and funding of the most frequently cited papers in medicine: database analysis

Patsopoulos, Nikolaos A, Ioannidis, John P A, Analatos, Apostolos A

Objective To evaluate changes in the role of academics and the sources of funding for the medical research cited most frequently over the past decade.

Family-Based versus Unrelated Case-Control Designs for Genetic Associations

Evangelou, Evangelos, Trikalinos, Thomas A, Salanti, Georgia, Ioannidis, John P. A

The most simple and commonly used approach for genetic associations is the case-control study design of unrelated people. This design is susceptible to population stratification. This problem is...

Patient Outcomes with Teaching Versus Nonteaching Healthcare: A Systematic Review

Papanikolaou, Panagiotis N, Christidi, Georgia D, Ioannidis, John P. A

Published data do not suggest that the teaching status of a hospital or other healthcare facility alone influences the outcome of patients treated in that facility.

The case of the misleading funnel plot

Lau, Joseph, Ioannidis, John P A, Terrin, Norma, Schmid, Christopher H, Olkin, Ingram

Evidence based medicine insists on rigorous standards to appraise clinical interventions. Failure to apply the same rules to its own tools could be equally damaging

Evolution of treatment effects over time: Empirical insight from recursive cumulative metaanalyses

Ioannidis, John P. A., Lau, Joseph

Evidence on how much medical interventions work may change over time. It is important to determine what fluctuations in the treatment effect reported by randomized trials and their metaanalyses may...

Are amoxycillin and folate inhibitors as effective as other antibiotics for acute sinusitis? A meta-analysis

De Ferranti, Sarah D, Ioannidis, John P A, Lau, Joseph, Anninger, William V, Barza, Michael

Objectives: To examine whether antibiotics are indicated in treating uncomplicated acute sinusitis and, if so, whether newer and more expensive antibiotics with broad spectra of antimicrobial...

The Decameron of poor research

Berger, Vance W, Ioannidis, John P A

Most gracious readers, two boring researchers present a series of pitiful tales—covert and overt fraud, petty misdeeds, and misconceptions by honest and not so honest researchers, professors,...

Why Most Published Research Findings Are False

Ioannidis, John P. A.

Published research findings are sometimes refuted by subsequent evidence, says Ioannidis, with ensuing confusion and disappointment.

Local Literature Bias in Genetic Epidemiology: An Empirical Evaluation of the Chinese Literature

Pan, Zhenglun, Trikalinos, Thomas A, Kavvoura, Fotini K, Lau, Joseph, Ioannidis, John P.A

Using the chinese literature as an example, John Ioannidis and colleagues show that selective reporting and language biases occur frequently in human genome epidemiology

Large-Scale Evidence for the Effect of the COLIA1 Sp1 Polymorphism on Osteoporosis Outcomes: The GENOMOS Study

Ralston, Stuart H, Uitterlinden, André G, Brandi, Maria Luisa, Balcells, Susana, Langdahl, Bente L, Lips, Paul, ...

A large collaborative European study finds only weak links between a much studied potential genetic risk factor and bone mineral density or fracture risk.

Origin and funding of the most frequently cited papers in medicine: database analysis

Patsopoulos, Nikolaos A, Ioannidis, John P A, Analatos, Apostolos A

Objective To evaluate changes in the role of academics and the sources of funding for the medical research cited most frequently over the past decade.

Family-Based versus Unrelated Case-Control Designs for Genetic Associations

Evangelou, Evangelos, Trikalinos, Thomas A, Salanti, Georgia, Ioannidis, John P. A

The most simple and commonly used approach for genetic associations is the case-control study design of unrelated people. This design is susceptible to population stratification. This problem is...

Patient Outcomes with Teaching Versus Nonteaching Healthcare: A Systematic Review

Papanikolaou, Panagiotis N, Christidi, Georgia D, Ioannidis, John P. A

Published data do not suggest that the teaching status of a hospital or other healthcare facility alone influences the outcome of patients treated in that facility.

The case of the misleading funnel plot

Lau, Joseph, Ioannidis, John P A, Terrin, Norma, Schmid, Christopher H, Olkin, Ingram

Evidence based medicine insists on rigorous standards to appraise clinical interventions. Failure to apply the same rules to its own tools could be equally damaging

Open letter to the leader of academic medicine

Ioannidis, John P A, Ahmed, Tahmeed, Awasthi, Shally, Clarfield, A Mark, Clark, Jocalyn, Dandona, Lalit, ...

As their campaign comes to a close, ICRAM presents a challenge to academic medicine's invisible leaders

Selection in Reported Epidemiological Risks: An Empirical Assessment

Kavvoura, Fotini K, Liberopoulos, George, Ioannidis, John P. A

An evaluation of published articles reporting epidemiological studies found that they almost universally highlight significant associations between risk factors and outcomes.

Uncertainty in heterogeneity estimates in meta-analyses

Ioannidis, John P A, Patsopoulos, Nikolaos A, Evangelou, Evangelos

John Ioannidis, Nikolaos Patsopoulos, and Evangelos Evangelou argue that, although meta-analyses often measure heterogeneity between studies, these estimates can have large uncertainty, which must be...

Required sample size and nonreplicability thresholds for heterogeneous genetic associations

Moonesinghe, Ramal, Khoury, Muin J., Liu, Tiebin, Ioannidis, John P. A.

Many gene–disease associations proposed to date have not been consistently replicated across different populations. Nonreplication often reflects false positives in the original claims. However,...

Doctors’ versus patients’ global assessments of treatment effectiveness: empirical survey of diverse treatments in clinical trials

Evangelou, Evangelos, Tsianos, Georgios, Ioannidis, John P A

Objective To examine whether doctors’ global assessments of treatment effects agree with patients’ global assessments.

Reasons or excuses for avoiding meta-analysis in forest plots

Ioannidis, John P A, Patsopoulos, Nikolaos A, Rothstein, Hannah R

Heterogeneous data are a common problem in meta-analysis. John Ioannidis, Nikolaos Patsopoulos, and Hannah Rothstein show that final synthesis is possible and desirable in most cases

Measuring Co-Authorship and Networking-Adjusted Scientific Impact

Ioannidis, John P. A.

Appraisal of the scientific impact of researchers, teams and institutions with productivity and citation metrics has major repercussions. Funding and promotion of individuals and survival of teams...

Why Current Publication Practices May Distort Science

Young, Neal S, Ioannidis, John P. A, Al-Ubaydli, Omar

John Ioannidis and colleagues argue that the current system of publication in biomedical research provides a distorted view of the reality of scientific data.

Reporting and interpretation of SF-36 outcomes in randomised trials: systematic review

Contopoulos-Ioannidis, Despina G, Karvouni, Anastasia, Kouri, Ioanna, Ioannidis, John P A

Objective To determine how often health surveys and quality of life evaluations reach different conclusions from those of primary efficacy outcomes and whether discordant results make a difference in...

STrengthening the REporting of Genetic Association Studies (STREGA)— An Extension of the STROBE Statement

Little, Julian, Higgins, Julian P.T, Ioannidis, John P.A, Moher, David, Gagnon, France, Von Elm, Erik, ...

Julian Little and colleagues present the STREGA recommendations, which are aimed at improving the reporting of genetic association studies.

International collaboration, funding and association with burden of disease in randomized controlled trials in Africa.

Swingler, George H., Pillay, Victoria, Pienaar, Elizabeth D., Ioannidis, John P. A.

OBJECTIVE: This study aimed to assess whether randomized controlled trials conducted in Africa with collaborators from outside Africa were more closely associated with health conditions that have a...

The PRISMA Statement for Reporting Systematic Reviews and Meta-Analyses of Studies That Evaluate Health Care Interventions: Explanation and Elaboration

Liberati, Alessandro, Altman, Douglas G., Tetzlaff, Jennifer, Mulrow, Cynthia, Gøtzsche, Peter C., Ioannidis, John P. A., ...

Alessandro Liberati and colleagues present an Explanation and Elaboration of the PRISMA Statement, updated guidelines for the reporting of systematic reviews and meta-analyses.

The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate healthcare interventions: explanation and elaboration

Liberati, Alessandro, Altman, Douglas G, Tetzlaff, Jennifer, Mulrow, Cynthia, Gøtzsche, Peter C, Ioannidis, John P A, ...

Systematic reviews and meta-analyses are essential to summarise evidence relating to efficacy and safety of healthcare interventions accurately and reliably. The clarity and transparency of these...

Genome-Wide Association Studies, Field Synopses, and the Development of the Knowledge Base on Genetic Variation and Human Diseases

Khoury, Muin J., Bertram, Lars, Boffetta, Paolo, Butterworth, Adam S., Chanock, Stephen J., Dolan, Siobhan M., ...

Genome-wide association studies (GWAS) have led to a rapid increase in available data on common genetic variants and phenotypes and numerous discoveries of new loci associated with susceptibility to...

Strengthening the reporting of genetic association studies (STREGA): an extension of the STROBE statement

Little, Julian, Higgins, Julian P. T., Ioannidis, John P. A., Moher, David, Gagnon, France, Von Elm, Erik, ...

Making sense of rapidly evolving evidence on genetic associations is crucial to making genuine advances in human genomics and the eventual integration of this information in the practice of medicine...